The whole thing is done from within the vb.net addin, no code is in Excel because the user can open any sheet. What your explanation has left out is how the monitoring thread activates the import once the monitoring is closed. Plus we don't want to close monitoring until the user chooses to do that. Activating the import from the ftpmonitor makes everything run from within that separate thread, which was my original issue.
But thanks for the attempt.