question about head gaskets and oil and coolant mixing

[Robert W. Roe]

In December I had my shop replace the head gasket on my TE wagon. At that time the head was sent out to be oven baked and redone, since it was warped. They also replaced several other cooing system parts.
Within a week or so after they did the head gasket the radiator split open and the temperature got very close to 120 deg F once. They replaced the radiator.

Within the last week or so, its low coolant light has begun to come on. So far I've added 3 qts of coolant, and the last time what was in the tank looked brown, and previously I've seen droplets of oil in the tank.

My question is, should I expect the shop to redo the head gasket at their expense if that's what turns out to be the source of the coolant loss?
I don't have a very good feeling after seeing brownish liquid in the overflow tank.
The car goes into the shop on Tuesday, so I wanted to get some opinions from you guys.

Just wondering, and thanks, Bob