In a few weeks when work on 2.3.3 is complete and the release is stable, I'll update and see if the errors persist.
That said, there are definitely In-Use-By bugs that may be related and troubleshooting this type of issue would be MUCH easier if the Hibitat error logs indicated exactly which Variable Connector is generating the error.
2.3.3 is stable, and fixes dozens of bugs in 2.3.2. I recommend that you update now.
The problem with this sort of error is that it is unexpected by the code, and so it isn't able to provide the information about what device caused it. Usually, it can be fairly obvious just by looking at what connector device has been set in an app just prior to the error, using the app logs.
In Use in Hub Variables tracks the variable, not connectors. If you look at these connectors, do they show the correct In Use By information?
As for the errors in your logs, I am not able to reproduce this issue. Do these rules work correctly? I suspect you might have some sort of corruption, but I don't know what that could be. Could you try creating a simple single action rule that toggles one of these connector switches, clear your logs, and then show a screenshot of the logs after you run the actions (no need for a trigger, just run the actions from the UI).