You're not wasting your time at all, as PPT is a viable reward option. You don't mention if you want to go in Y or J, but both are viable options. The LAX-PPT route doesn't fly daily, so that will affect your ability to find seats there. On the flip side, you might be able to force-overnight in LAX if you want to add that to the vacation plan.

SkyTeam does not appear to have any member-coded flights into MLE. You might be able to use miles on EK, though I'm not sure if they are a DL partner; they definitely are a CO partner. SQ also might get you there on a DL award.

As for availability, you can try www.seatcounter.com. I believe that AF J awards book in to "O" class. It actually looks like the flight next Thursday (8/16) is showing O9 in Seat Counter, so either there are a lot of seats available for reward, seatcounter is wrong or I have the wrong fare bucket.

Last time I called in to Dl for the LAX-PPT flight they were pretty good about checking dates and working the system to see what they could find. They are used to it.