Hello and welcome to the forum.
Presume you have pre-booked tickets (for the persons travelling) with seat reservations for a particular journey.
If you are willing to do so, can you advise the details of the journey, such as...
Date of travel,
Ticket type,
Start station,
End station,
Time of train,
Seat reservation number(s) (if known),
Train company (if known),
Class of travel, such as Standard or First Class,
and our forum experts should hopefully be able to determine which type of train they are likely to be travelling on, and whether or not those seats on that train do have the additional room that you've hopefully booked.
P.S. It's possible that the asterisks to which you refer means that for all or part of the journey, it's on a train with "counted places" only, and that no individual seats reservations are normally possible or indeed have actually been issued, in which case although your friends may have to use that individual train, it will, however, be on a "sit anywhere" basis.