So, two or more users can't share a single VPS or PC?

For example, if my friend have MetaTrader account (registered under his own username) and he is hosting my MetaTrader (registered under my username) on his PC or VPS (to make the trade copying working correctly or to act as "forex manager"), is this a violation of TOS?

For this to work do I need to ask my friend not to open account at your site (to use different forex broker) just to be sure that the TOS is not violated?

"Every person can only be operating one username"

I have another account I am not using, I signed up just for testing (to see the platfrom from the "inside"). There is no option to delete it when I searched. Can I just leave it without real trading activity?