And more to the point, the cleanroom scenario were some people producing an 'interface specification' working backwards from the binary, not decompiling it. If they had decompiled the source code and passed that on, that would not be cleanroom.
This also hinges upon the 'cloned' bit being an ABI/API, which by itself is not considered substantial enough for copyright protection.
So the concept of an AI decompilation of a whole application being considered cleanroom and safe is a bizarre concept that seems to spring from wishful thinking rather than anything vaguely realistic.