Mavis Discount Tire review: Oil change that resulted in having my engine replaced

I had an oil changed done. The tech did not secure the oild filter, resulting in the engine being drained of the oil ultimately resulting in having the engine replaced.
Mavis made good on the engine replacement however the engine is leaking oil and now Mavis is not responding to my requests. I also have not received a warranty on the engine and or the auto shop that performed the engine replacement.