Substitutions (I have not tried these personally but here are some options that I believe should work):
* typically oat flour can be subbed for almond flour or regular flour 1:1
* sub 2 flax eggs for the regular eggs (2 tbsp flax seed meal mixed with 1/4 cup + 1 tbsp water, let sit for 10 min)
* vegan whipped cream cheese options should work in this
* typically coconut sugar can be subbed for brown sugar or regular sugar 1:1
* for crumble: you can use coconut oil in place of butter