I think this is a new failure mode for WiredTiger, where the cache is "stuck" with clean content but the verbose cache dump suggests that it isn't stuck. WiredTiger appears to think that it is as the tracked bytes in cache are significantly different from the actual amount found in cache.

e.g.

cache dump: total found: 0.01 MB vs tracked inuse 163.06 MB 
cache dump: total found: 0.01 MB vs tracked inuse 247.86 MB 

These come from two failures seen recently on WT-11372. This ticket is being created as this seems like a new failure mode.