Hopefully that dealer didn't take the machine apart and ruin it. I'd collect it as soon as possible, take it to your original dealer's technician, get a detailed invoice of what he/she does to the 11000. I'd then be tempted to take it back to the "bad guy" and show him/her what scammers they are.
I like you gave my 11000 to my daughter back in 2014 or so and she runs it with no issues. I almost got myself into a pickle here as I also gave my MC6000 another daughter for a wedding gift, as it was better than most new machines of the price I'd get to sell it - that was in 2004, and she still uses that machine to hem her pants, mend what needs mending and I KNOW that machine hasn't been in for a service since I had it serviced to give to her. As for the 11000, I also know that it hasn't been in either and both work just fine. Yours should too if that twit hasn't messed with it.
I hope that you can get this resolved so that your daughter can enjoy lots of "good" sewing and embroidery with her gift from you.
Cheryl - Saskatoon