More importantly, I believe that the burden of proof is on the accuser, and so far the only thing the've done is filing DMCA takedown requests. Which have a notoriously low bar for what constitutes "evidence", thus making it a very useful instrument for harassment.
Unless we discover that the developers simply lied in their official statement on the issue, the current situation seems like a fairly typical DMCA abuse case. Since they are planning to fight the DMCA takedowns, I expect we will find out the truth soon enough.
Disclaimer: I am not trying to write some anti-DMCA manifesto, but just to simply illustrate the reality of the situation. DMCA is an imperfect solution to a problem, and I believe it certainly could be done better and/or improved. However, it is easier said than done, as I don't have a proposal in mind for a better system. Getting rid of DMCA entirely without introducing a replacement mechanism is just going to open up another problematic can of worms, so I am not going to advocate for that until I have something better in mind.