Obviously, it's not that great a concern since they "sold out".
The DDM line had some real problems with size creep over the line. There's some halflings that near the end of the line that could have been used as human figures in the Harbinger set.
Maybe, maybe not. They may have not produced many minis for their first run. That could be why they sold out.
Or it may have been a case of many DDM collectors giving them a go to see what they were like (especially since they don't have DDM to spend their money on any more). After buying the first set and finding that they don't match well with DDM's they may decide not to buy any future sets.
Alternatively, they may have produced a huge amount of minis and been more successful beyond their wildest expectations. Without us knowing the numbers we're just wildly speculating, not that wild speculation isn't fun!
In regards to size creep with DDMs, I am fully aware that there was issues with that in the line. For example, the Guard of Mithral Hall dwarf mini is a prime example of a sculpt being too big. It was so big that I know many people repainted it as a statue because it just looked ridiculously large next to the other Dwarf minis in the line.
WotC was criticized for those issues and I fully expect Paizo/WizKids to be too. The fact that they have admitted some minis have these issues and will be trying to correct it for future sets is definitely a step in the right direction.
How long has DDM been out of production? Guys like you and I probably do have plenty of them, but Pathfinder isn't completely aimed at people like you and I. Hence the Beginner Box.
Firstly, the size/scale issues have been mentioned and supposedly will be corrected in future sets. I trust that future sets will have better scaling and better paint jobs. Harbringer had some awful scales, sculpts and paintjobs too.
Secondly, I seriously doubt most people will go with your answer "C", since the initial production run sold out of manufacturer's stock in only a week and a day. Personally I fall under "A", and I think many other "old timers" do too. But I would add a "D" category: people new to the hobby looking for minis to supplant/suppliment the pawns from their Beginner Box.
I know that the Pathfinder minis aren't solely aimed at DDM collectors. I'm sure that Paizo will get quite a few people that have never bought pre-painted or unpainted minis before that will give these a go, simply because they really like most or all of what Paizo produces (even though this is technically a WizKids product).
Having said that, in terms of scale, some of these people may buy a few boxes or bricks of minis. From my experience DDM collectors tend to go in pretty large to these sorts of things, buying enough to either get 1 of every mini in the set or, in some cases, multiples of every mini in the set.
I know that many DDM collectors may have decided that enough is enough (I own a few thousand DDMs and I am close to, if not in, that camp). However, I expect that there are many others that figure they don't have anything better to spend their money on now that DDMs aren't being made so they will buy these instead.
I guess time will tell as to what option most people fall in. However, even if there aren't a huge amount of people in option C, it still makes little sense to me to deliberately make the minis of a different scale to DDMs (not that I think Paizo/WizKids have done that on purpose).
So I guess what I am saying is that getting the Pathfinder minis on the same scale as DDMs will only increase sales further, which can't be a bad thing from a Paizo/WizKids perspective.
Olaf the Stout