Well I dunno if you have scanned all the posts here regarding to soundbars. Sounds simple, but high probably you buy the wrong soundbar that is not compatible for recipient's TV.
U want to know what kind of AUDIO OUTPUT is available on TV, and have the matching INPUT on the soundbar.
In addition, you want to know whether those outputs are VARIABLE or FIXED. Fixed output says you must have volume control on the soundbar.
Furthermore (phew! u thought this was going to be plug&play), hookup through HDMI, if you determine this interface can be used on both pieces, the TV remote CAN (but not always) control volume on the SB, otherwise your family will have to use 2 remotes, or a universal, for the 2 pieces.
Enclose a receipt, so they can exchange if at all possible.