Don't get me wrong. I like Dungeon World a lot. It's one of the systems I'll run when I want a more cinematic / scene framed games. It is just not as immune to DM force as you often present and that force can be at least as difficult to pick up on as Illusionism is in more outcome-based games like D&D. The power of the DM to pick the resultant moves that fit the narrative is central to the game and can be easily used by the DM to garner a particular play experience. This is beneficial when the DM is using it to maintain a genre convention. It is more problematic when the DM wants to take a game in a particular direction.
Your first example (copied below because the board doesn't do quotes in quotes) appears to be a great example of GM force moving resolution / scene framing towards a specific goal.
Saerie is attempting to win over the dog and outright fails. Which should presumably take the dog out of the scene as an ally/friend. A hard move of Harm is probably unwarranted considering the fiction, though not completely out of character for the animal type. A more typical move would be for the animal to snap at the person, grab the food, and hightail it leaving the two-leg to flounder in the snow. Instead, the move chosen a soft one: the introduction of a previously disclosed (but unconnected to the current scene) environmental hazard that is approaching, but does not require instant reaction (the herd is still far). So the failure -- which would be immutable as a hard move result -- is negated. The DM keeps the dog in play as a potential friend/ally and even signals the animal is still approachable through the description of body language and positioning. Sort of "You failed, but the universe is worse than you so try again".
One might begin to think the DM wants the dog befriended/rescued.
Good. This is exactly the kind of stuff I wanted to talk about.
So here are my thoughts on the above situation. First, the
Fiction:
1) Starving, old, deaf sheepdog that has been living in a state of trapped terror for who knows how long.
2) What would a creature like this want? Food, companionship, safety.
3) The Ranger knows animal posture/behavior, entreats the dog with an appropriate show of lack of aggression/sincerity, offers food.
4) That is very powerful leverage in this situation.
Mechanics:
1) Unlike Fate, Cortex+, 4e, DW (and most PbtA conflict resolution) doesn't have formal closure to every scene trope (save for where clocks and things like HP are involved). So here we're just left to follow the game's Agenda and Principles rather than closing out a scene. A few moves will pin you down tightly on a 6- (this thing happens). Most, Parley included, leave it open for the players (through their action/inaction), the fiction, and GM fidelity to Agenda/Principles will tell us when we're done. It certainly isn't a system that mandates for binary responses to moves; a or b are the only permissible outcomes for success failure. In fact, it expects the opposite.
2) This dog would yield no danger whatsoever to the Ranger (Starving Old Dog @ 1 HP, 0 Armor, w[2d4-1] damage. Instinct; to cower in fear or run from danger). If she wanted to kill it, it would be a trivial thing to do so.
3) So having it be aggressive toward her (a) doesn't make a lot of sense to me and (b) doesn't yield any action/adventure/danger.
All together now:
So then, given all of the above together, how do I resolve this situation? Further chase is boring. And she is on top of it, she could track it down again no problem. That doesn't change the situation enough. I look at that sort of resolution in the same way that I look at people who fail to dynamically change the situation in a 4e Skill Challenge and then blame the system for the uninspiring play results ("the king looks uninterested in your in your historical account of his family's oath to take in the refugees of war").
What does Saerie want? She wants to functionally communicate with the dog. What (a) most threatens what she wants, (b) follows from the fiction, and (c) ensures that the game/her life is filled with action/adventure/danger?
To me, the answer is something that will take the dog out completely. I put maddened animals and mutates on the table as an ominous portent earlier in the game. So, how about a herd of stampeding reindeer? Maybe they're mad. Maybe they're running from the coming storm. Maybe something even worse is chasing them? I don't know. However, what I do know and what Saerie's player knows (and obviously Saerie within the fiction) is that a stampede (10) of monstrous reindeer are an absolute deadly threat to a level 3 Dungeon World character. If she has to engage them by herself on the open tundra...it is very, very likely curtains for the PC. And (Far) as a range band isn't significant for a reindeer (you're talking up to 50 MPH in our world). So while they're not "whites of your eyes" range (Near), they are what would be the fictional equivalent of "right on top of you in short order."
She could most likely get out of this pinch on her own, but the dog is a liability here. So I'm basically just proposing the question of "what is this worth to you? How much are you willing to put up for this?" This is the sort of advance/escalation that I would do in Dogs in the Vineyard and I think it applies best (all things considered) here.
So while this is effectively "Show signs of an approaching threat", it is the most amped up version of "approaching threat" as you can legitimately get away with (I did the same with a Rhemorraz later but I foreshadowed it aplenty before). It is a lethal threat to not just the asset she is trying to secure, but also to the PC herself.
QUICK EDIT - If the player would have used aggression as leverage (eg "I advanced threateningly and corner the dog, hoping it will go belly up and submit), I would have definitely attacked. Attacking would have removed the prospects of gaining the dog as an asset (as it would have effectively been suicide).
The context of Leverage/approach, the greater fiction (including the creature's Instinct) surrounding things, and how best to achieve action/adventure/danger (not just to the PC but toward thwarting its intent), means a great deal for the follow-up move that should be made on a 6- Parley move result.