I went to the Halal butcher the other day and asked for steak, except what I received was more like thinly sliced beef.
What can I do with this on a barbeque? Will it cook the same? How can rescue the situation?
You can definitely still cook it on the barbecue, just don't' cook it as long because the heat has less distance to penetrate. You can also try flipping the pieces more often so each side isn't exposed to the heat for too long, it can't penetrate too far into the meat before it is flipped over and begins cooling. This should allow you to get some nice crusting on the outside and keeping it juicy in the middle.
Get that bbq SUPER hot.
Sounds like it's time for a steak sandwich. Grill it up in a frying pan, add some cheese and top with sauteed onions, mushrooms and peppers and serve it on a toasted baguette. You said the steak was thin, so make sure not to overcook it. Cook up the veggies first, then the steak.
No idea if its halal or not, but it sure will taste amazing.