well I've emailed teamviewer for this problem long time ago and their response was something like : "teamviewer cannot provide screen if you dont have attached one" . Using dummy plug basically very often results in losing hashrate for one of the cards since it occupies some resources of itself and lowers its performance. TV worked in older versions though , dunno what they changed , I told this also to them . I guess only being premium/paid TV service you can get decent support. I suggest you use some kind of 2nd "watchdog" such as ethmonitoring/awesomeminer stuff in which you can configure your rig with basically minimum of using teamviewer. Good luck