Okay you can do the private match glitch to get xp by:

Inviting a friend
They go to there playercard
You switch the lobby to combat
Backout
They invite you back
Then they switch to wager
Then back to private and it starts up

Theory part:
What if you did the search and destroy glitch or demolition glitch in combat training in this process?

Would that make it possible to demo boost in private match???