Originally Posted by
ratypus
Not sure I understand what you are trying to do...they are flying to Vegas out of T3, but you want them to have lounge access so are interested in other short-haul routes out of T3?
How do you see that working? They can't really check in and meet conformance for both flights, if that's what you had in mind...(to get them into the lounge on the short-haul business class ticket then fly on the long-haul ticket with no lounge entitlement...)
I think the OP wants to fly to a short haul destination from T3 and guest their family who are flying longhaul into the lounge, which is perfectly feasible.
Although it's not relevant to this case, there is no conformance in T3 (just the usual check-in and gate closing deadlines).