Okay so I know nothing about cars and my husband is out on deployment so I need advice...

I have an 04 S4 4.2 V8... car was great but I went to get an oil change. Two days later it was pissing oil out the back of the engine. Took it to the shop and they are saying it’s the oil sending unit hose connection and it’s $1100 to fix. I am just wanting to make sure I’m not getting screwed and paying for their mistake. I’ve topped off the oil before and it wasn’t leaking before the oil change.

Any advice?