The group didn't get any XP for "fighting" the beholders, since they hadn't; really all the scene did was establish friendly relations with the bronze dragon.
Uh, to "soften the blow" a bit couldn't you give role-playing XP for establishing friendly relations with the dragon (since that seems to have been part of the "story goal") rather than roll-playing XP for fighting?
Anyway, using Shroedingers cat is the method of not deciding something plot-sensitive until you are forced to (as DM of course, but it works for any storyteller).
Agreed, that's not my kind of style either. For starters, I'm obsessive/compulsive and not knowing such an important detail as who the murderer is in a game I'm running would drive me nuts, very likely impeding my DMing of that session.
Though I think I might not mind this kind of thing for one-shots or if the DM had to improvise most of that particular gaming session anyway (assuming it's not the norm and, if it's going to greatly impact the NPC/faction/whatever who "is it," isn't done with someone who's too campaign-important).
Uh, to "soften the blow" a bit couldn't you give role-playing XP for establishing friendly relations with the dragon (since that seems to have been part of the "story goal") rather than roll-playing XP for fighting?
That was included in the overall XP they got for the session, yes. My point was just that since they were not in "real danger" from the beholders (who got scared away almost immediately), they didn't get XP from that particular piece of the encounter.