I think it is possible to sue them if they refuse to help you?
You have proof that they ignored your messages for days on end, and marked them as solved without giving you a refund or a response.
I don’t know much about law stuff since it’s different in every country and I don’t know by heart Episode’s policies and stuff so you should search it up.
Yes, $10 is indeed too much to spend on a mobile game especially when something like this happens.
I say wait a few more days and if not, you can try a different way to get your money back.