WDW no longer carries Lays chips. They now have their own line of WDW potato chips. I do believe that they're gluten free but they're a kettle style chip which is something my kids don't like which really stinks. Lays chips used to be a stand-by snack for us.
Divvies cookies are not gluten free. The Divvies jelly beans and caramel corn are.
The frozen pineapple bars, strawberry bars and Itzkadoozie popsicles at the ice cream carts are also gluten free. LOVE the pineapple bars.
You're already aware of the Enjoy Life cookies and the French Meadow brownies and cookies. Popcorn's also a staple snack food for us as is fruit.
Sunshine Seasons has Enjoy Life chocolate bars with rice crisps.
My kids get plenty of ice cream at WDW. Just make sure you let the person serving know about the "allergy" and it'll be scooped from a fresh carton using a freshly cleaned scooper. In our case we get dairy free ice cream so I can't be sure if the regular Edy's is gluten free or not since it's not something we can eat anyway.
I think you may still be able to get the flourless chocolate cake at Starring Rolls in DHS.
We got a birthday cake from Babycakes in February. DELICIOUS!! An added bonus to it being safe for my girls with laundry lists of allergies is that my DH who's a T2 diabetic could eat it without blood sugar spikes since it's sweetened with agave nectar instead of sugar. The cake was VERY expensive ($45 for a 6" cake) but so worth it because this was the first birthday cake she's ever had not baked by me. I think I read that the cupcakes are around $3.50 each so very much in line with the rest of WDW pricing (that's cheaper than the cupcakes at Starring Rolls at DHS).