I've got the same issue, updated to IOS-XE 3.3.3 and despite an SNMP walk showing the correct values, the Orion chart showing the correct values I'm still getting warnings.
I suspect Orion must be also monitoring another SNMP MIB then just the temperature value (a monitor state MIB?) and it's either being incorrectly reported by the switch or incorrectly interpreted by Orion. I've just logged a case with Solarwinds support with an SNMP walk so hopefully they can nail this where it's going wrong. I'll try to remember to update this when I hear back from them.