@mcalnd,
Thank you for bringing this to our attention.
I just tested on CM 5.13.1 and 5.15.0.
I changed the percentage from 90 to 91.
After about 10 seconds, both YARN services showed the configuration was stale. The diff showed the change I made
I wonder if there may have been a problem with the staleness detection in CM in your case.
If this happens again, you might try restarting Cloudera Manager and see if the stale config is detected and then review the CM log to see if there was anything going wrong with "staleness" detection.
Thanks again!