While I’m not a mechanic I have been a gear head my entire life. Here’s my opinion: At the least this has added thousands of miles of ware to your motor. At worst you will need a total rebuild of all bearings, crank work, cam, cylinder bore, new pistons, etc….
This may end in a lawsuit so I would document everything. I’d video tape the oil trail, make sure you have proof of the oil change and have it towed too a good mechanic who can run compression tests and oil pressure test (especially at idle). There are also oil tests that can determine how much metal is in the oil which will indicate wear. They also need to document where the leak was and that it was the oil change companies fault.
I would NOT take it back to the oil change company since they will say it’s not their fault and you somehow damaged the motor. An independent mechanic is the way to go.
Good luck.