My advice is to talk with your Scoutmaster. If he/she is taking the troop out camping in temperatures of 10 F, he/she - or some other adult leader in the troop - should be well trained/experienced in cold-weather camping.

Unfortunately sometimes the person doing the training & preparation in the troop focuses so much on the youth - for their own protection - that he/she forgets to also train the other adult leaders.

I've never heard of someone succesfully cold-weather camping on a cot, but given enough insulation between you and the cot, it should work OK. It sounds like your gear is reasonable (lots of ground insulation, sleeping gear insulation, dry non-cotton clothing, supplimental warmth from your bottles, etc ...

Have fun!!