Use the user profiles feature of grapheneos to make a “social” profile and only use that to access Instagram / facebook.
You’ll want to consider isolating IG from your primary profile, to start. The above user’s suggestion hits the nail on the head.
Once the profile ks created, and you’ve installed IG, you’ll want to deselect the option in your Manage Profiles settings on GrapheneOS to ‘Allow running in the backgroud.’ This way, you can ensure the app is entirely stopped until you want it open.
Another consideration may be to turn off your Bluetooth when it’s not in use, as well: BT emits an ‘address’ of sorts that, if another IG user has enabled BT access on their IG app, may be able to detect your phone and track a conversation knowing you are in the other user’s vicinity.
Unless you have built your own custom version of wine, and/or you don’t remove your wine directory between versions, you can always install a different version of wine and try it out.