Ms Travel

We have had ocean view rooms with pull down beds from the ceiling.  Is that what you have?   Yes, it is tight, but you will save $$ over booking 2 rooms.  Then you can use the $$ to extend your vacation before or after the cruise, try more exotic excursions, etc.  If you can get a cheap balcony with sofa bed, the kids can do that instead of the pull down bunks.  Sometimes there isn't that much difference between ocean view and balcony, depending upon your Crown and Anchor status. 

There will be no room for a separate cot or bed even if they would bring you one.
I agree with you...that is going to be a very, very tight squeeze.
I would seriously consider either upgrading to a larger room category or booking a separate inside room for the boys.

They do not have this set up on every boat.. They usually only have this on Oasis Class Ships and Quantum class ships.. Older ships usually have just a regular pull out couch.. 

We always get one room with no issues.   The sofa pulls out like a trundle so there are 2 distinct beds.  Our teenage boys sleep just fine on them.  No complaints at all!