As proven time and time again, the poeple writing the T&Cs have no clue how the real world really works (except maybe AA if you believe their ads). If they were written clearly there would be no need for FT.

I have never yet known a property to do a bed check. When I have two rooms at a property, I check in and get both sets of keys. I choose who is in which room and if I choose to give up the suite to my sister and her husband, that's my choice (although I make sure I keep a key with lounge access when available).

Knowing how some CSRs work, having the paid room as being "MY" room should make getting the double points and all a no brainer even for the least trained person. If there's a chance a third room won't post to your account I would book it to another account (parents, spouse, etc).

As the saying goes: The difference between tax fraud and tax avoidance is 20 years. Don't throw credit/points away if you can help it.