Call these rooms what you like. You are the appraiser; not the building inspector. Just make certain that you tell the client exactly what you have told us.
If you think there is a problem, advise the client to have the rooms inspected by the local building code enforcement agency.
As to the market reaction, if there are no comps, you have to decide and make a professional estimate as to the market reaction to this non-typical floor plan. On the basis of that judgment, you also have to decide if you are going to call these rooms bedrooms or not.
Do not call them bedrooms. Like Richard says, call 'em anything you want except a bathroom. I have great difficulty following what all the initials stand for. Spell them out! Adjust for differences in square footage. A sitting room, for example, is a desirable feature in my market area. They could be studies.... or a media room and a den, or any combination.
NO one in this market is gonna call the other rooms 'NOT BEDrooms'.
Nah it is an 'other'.