You will be laughed out of the door if you ask for a refund or compensation. This isn't America.
Some cars are just a pain to bleed unless you have the correct vacuum pump.
All they can do is fix their mistake. I reckon you would still be ****ed off asking for a refund if they were a day late.
To be fair the owner was there waiting for them to finish off so they had no time to run it up to check it properly.
I'm just hoping the OP hasn't cooked it up & borked the head gasket but as the garage now says it's not overheating it sounds Ok.
Dodged a bullet I reckon.
Why the hell is it still running while you took the photo?

You will be laughed out of the door if you ask for a refund or compensation.
Airlocks happen.
Just one of those things....
Not really. The workshop should have refilled and bled the system, it's not difficult.