Apples are generally considered "safe" for GERD, so it is either the fat in the pie crust (a possibility, looking at your list of trigger foods) or the sugar and spices.

Sugar is the #1 trigger in my GERD. Some spices also are triggers for reflux.

Apple "crumble" pie can be deliciously made without sugar by substituting unsweetened apple sauce for the sugar, experimenting a bit w/spices, and by substituting an oatmeal based crust recipe that doesn't use lard.

Sadly, what most of us are addicted to is fat and sugar, or fat and salt. So I suppose GERD serves us right, eh? (Or at least those of us who consume jellied eels--duck!)