Assuming you are using this
https://vborg.vbsupport.ru/showthread.php?t=173239 for mobile detection? If so, when a sidekick user is online, check their useragent string in teh Who's Online section. You can then pick a unique piece of this and add it to teh exceptions.
A quick google and it looks it the UA string will be: Mozilla/5.0 (compatible;AvantGo 3.2 ProxiNet; Danger hiptop 1.0)
If this is the case, probably add "hiptop 1.0" to the exceptions - I believe Danger Hiptop make the sidekick? Liek I said - this is from 30 seconds of research, so double check and test!
Hope this helps -