That license looks like a minefield. Any lawyers able to chime in on the reality of becoming tainted? Given their recent history, this is one codebase you really wouldn't want to risk becoming tainted by.
Crytek v. Cig, which the court ruled largely in favor of Cig, and even called out Crytek's behavior (which was an absolute circus). Crytek will prosecute given even the most questionable grounds.
The consequences of taint are a very real risk here.