That plugin must be implemented strangely if it needs an entire base actor class to pool with, you should easily be able to create your own pool system, they are very simple, its just spawning as needed (need more than current pooled count) and not deleting but deactivating and re-using.
Regardless, you are likely dropping it, default settings will drop on trigger release which will override the use command.
Set drop on grip or something else so that it doesn’t try to drop it instead of use it.