Given your LMS version, seems you could be hitting CSCsm97530 regarding your 6500s. I am also seeing some ENTITY-MIB related issues (could be CSCeb51407). This can affect a device running anything below 12.1(19)EA1. My suggestion would be to move up to latest LMS if possible (3.2). If you go that way, beware of CSCtb16925 which could be the follow up problem on your 6500s. You can open a TAC case to get a patch for that or for the applicable ones on your current version if ugprading is not a possibility.
Yes, that looks pretty close to the issue. Looking at your logs again seems CSCsv65621 is involved. There is a combo patch for both these bugs (CSCsv65621, CSCsx58694) on RME 4.1.1 which you could acquire via TAC. If you can move to LMS 3.2, that would be preferable. You can apply patch for CSCtb16925 on RME 4.3.1 if problem resurfaces there.
We are pleased to announce availability of Beta software for 16.6.3. 16.6.3 will be the second rebuild on the 16.6 release train targeted towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are looking for early feedback from custome...