Would MP2s be corrupted if they were added APE tags??

properly written mp2 stream reader (working pretty much the same way as mp3 stream reader) should recognize ape tags as bad data and ignore them (thanks do id3 mess, every mpeg reader out there has mechanisms to handle that), much like with id3v1 tag at the end.
there's no significant difference between potential problems with ape tags in mp3 and mp2.

That's nice to hear, thanks zZzZzZz .