I think you're on the right track. Only a few suggestions, off the top of my head. Contact David's in April or May of this year to let them know what you want. The
DVC owner can't make the reservation until June, but knowing that a request like that is coming might help David's people get something set up ahead of time to make sure you get your request. Another suggestion is to understand that you can't (or, really I guess, shouldn't) make any airline reservations until you have that room reservation in hand - the odds of you being able to move it even one day in any direction are slim to none. I think that's why you mention the potential for a couple of days at a different resort, but I wanted to stress how 'set in stone' a DVC reservation is. (I'd usually say 'set in jello' but that gives the impression it can actually, with enough effort, be moved. Since you're not the owner and you're not the middleman but yet another step away, it would be *really* difficult to get it changed.) Another suggestion, which you seem to already be doing, is just to read as much as you can on these DVC boards about DVC in general and AKL in specifics. I'd also encourage you to look for the AKl thread(s) on the resort board. And, finally, bring salt and any other spices with you when you come as those aren't usually to be found in a DVC room. (Someone recently said they usually got rooms where people had left such stuff; I've never been that lucky.)
I hope you enjoy your trip!