Welcome to FT, NotVeryOften!Yes, easily, if you go your separate ways when you arrive: you through immigration and customs to landside, she through the transfer route to the lounge.

I think, though, that it is a little more complex if you want to go through the transfer route with her to actually take her to the lounge, and then reverse back into the arrivals stream to exit through immigration. ISTR there being some recent complication in doing this, but hopefully someone who knows more will post here.