Raw Evidence Type = Uninstall on RHEL device
Uninstall raw evidence type is on the dark side, few or not documented. In principle, trace on uncomplete unsinstall action.
On windows, often remaining key in registry.
On Unix, not clear but uncommon. I suggest to have to a look on all raw file evidences, on the device via UI. If nothing, you have to have a look on the device it-self.
Most installer evidence on an RHEL system is likely to come from the RPM (RedHat Package Manager) database.
The specific evidence you're looking at here is related to IBM DB2, so it is possible in this instance that it has been gathered based on output from running the db2licm license management tool.