They do the best they can. Be aware, though, that HH is usually absolutely FULL during this time of year. Getting what you want will not only depend on those checking in, but also very greatly depend on who is checking OUT. If the location/room you wanted has someone in it that has been there for several days and isn't leaving for several more, there is no way for the poor CM to give you the room.
We were at HH just about a month ago. I know it was 100% at capacity as we had to waitlist just to get 4 nights together (and I requested ANY 4 nites in June). The last one didn't come through until 3 weeks out. Anyway, the day after we checked in I walked into the main lodge for some literature and watched as some really obnoxious guest just absolutely reamed out a CM for not giving him the room he wanted. This guy was loud, sarcastic and all of it in front of his 2 young boys (what were they learning there - to pick on the help?). The CM was as mild and patient as she could be explaining that requests were not guaranteed. She should have got a medal!
Anyway, go ahead and ask, as they really do try. But don't shoot the messenger if you don't get everything you want.