commercially releasing unmodified freeware is surely not ok, but even if - IF - part of the game is based on freeware
That's not even possible. Quantum Star / Solar Empire is a PHP browser-based game (a clone of the old Tradewars / TW2002 BBS game, by all appearances). Entirely different language (PHP vs C), basis (BBS-style text game vs 3D RTS), core game mechanics... pretty much everything, aside from being in space and with "solar" and "empire" in the name. Which is hardly unique to either game.
The OP makes serious accusations, though. Personally I'd expect someone to do a bit of research before making such claims.