Yeah, so I noticed some things I wanted to change in the tags of today's Alex Jones show when listening in foobar, so I open my trusty Mp3tag and, uh, there are no tags displayed!
This is not a bug. Like you assumed, the APEv2 tag is causing you trouble here because it only contains the ReplayGain values. If you set Mp3tag to read APE tags, it will favor them over the ID3v2 tag that contain all the other information. Simply deactivate APE tag reading if you want to edit the title, artist, etc. information for those files.