Hey Jamie,
Looks like a minor bug in remote MySQL database support, as discussed in this thread:
http://www.virtualmin.com/forums/message-view?message_id=65818
In short, the user created on the remote machine sets up to allow "user@localhost" to access it, but the user, her scripts, and her administrative tools, are actually gonna be coming from "virtualminserver.tld".
Status:
Closed (fixed)