Since my findings were deleted on the threads of the actual videos, here are some non-incompetech songs Wendell has used from the YouTube Audio Library:
Wendell has been preaching incompetech for a while but recently some songs have been taken from the YouTube Audio Library:
The first mellow organ one you may have heard is this one:
Rhodesia by Twin Musicom: (Creative Commons Attribution license)
Another one that has a good beat is this one:
Hanging Out by Bruno E. (Exclusive to YouTube Audio Library)
From the Recent @eposvox video:
“Sleeplessness” by The Brothers Records (Exclusive to YouTube Audio Library)
From the AMD vs Intel “which CPU should you buy” Q3/Q4 2017 video:
“Love Struck” by E’s Jammy Jams (Exclusive to YouTube Audio Library, same artist as the BG music in Getting Over It with Bennett Foddy)
Those are the major non-incompetech songs so far.
“Rhodesia” actually requires different Creative Commons attribution than the incompetech attribution at the end of the copy/paste for each video. The rest seem to be CC0, so no worries for those songs.