I also found this problem with my chest bevels too. I used a modified version of Kent’s solution to fix it. Essentially just correcting each plan individually instead of trying to correct the entire chest as a whole.
In edit mode, I selected an individual plank with ‘L’. Only select one plank at a time.
Hit Alt-M for “Merge Vertices”, then select “By Distance”.
Repeat for each affected plank.
Fixed the extra vertices in each plank and I’m now applying the bevels as expected.
