I'm confused???
Why wouldn't you just use your chase card to make payments? you'd still earn credits that way.
One HUGE caveat.... if you cancel your trip, all of those payments are going to be returned to you on Disney gift cards. Personally, I would not want to tie up a large amount of money on a gift card. To each his/her own, but I would rather have the credit to my credit card. I travel to WDW pretty much yearly, but the thought of having that much money just sitting there on a GC makes me cringe...
Just trying to give you some food for thought... not start a debate about whether someone should or shouldn't....