I'm actually staying at the Hilton Parc Soleil early next year with the timeshare promotion. I called Hilton to change one of my reservations and was asked if I'm interested in a promotion they had. I was "specially" selected (didn't believe it but I went along). I wasn't able to get much out of it (only 15K points and $100 certificate after the trip). Probably should have pushed for more.

Maybe try calling them to see if you can get the offer that way. I don't know if they will offer it on-site.