Honestly they should leverage their ties with Tencent and push it as an alternative OS in China get a large foothold there then expand out. Their dislike of Apple and Distrust of Google are pretty well known so getting in good there now would cement a large user base and let them branch from there.I think it's an important fight, but using Fortnite as leverage to try to sue Apple, I don't know. Not a great strategy.
I think noko is right about innovation. Maybe Epic should have spent that money making their own Android fork OS, or their own phone. They have the cash to do it.