Could a performance chip have caused my engine to fail?

Morning
In 2016 I bought a 2013 535i from a California CarMax and had it shipped to
Myrtle Beach SC. Had 13k miles on it at the time. Now has about 50k miles
on it. I installed a Berger performance chip and cold air intake a few months
after I bought it. Car was under warranty till 2017. Then bought extended
warranty through fall of 2019. All service was done at the Myrtle Beach
dealer. They never complained about the chip being on there. Car came due
for oil change in January of this year. Since I am now out of warranty I took it
to a Firestone. Got a call from them a few hours later saying that after they
changed oil the starter would turn but engine would not start. They tried to
tinker with it for 2 days and then had it towed to the local BMW dealership.
Dealer kept it for few days. They called me back and asked me to approve
further diagnostics that would cost $600. They said they replaced spark
plugs, drained the oil again (supposedly just replaced by Firestone) but
came out totally black. Still no go. The next call I heard all kinds of stuff
about too much gas in the cylinders, fuel injectors stuck open, metal
shavings in the drained oil, engine needs to be replaced. And of course
everyone is blaming the chip now. I don't know if the chip is at fault since all
it does, to my understanding, is optimize the fuel/air ratio to improve engine
performance. Even if they are right, shouldn't BMW, having done all the
preventative maintenance prior to this, have seen the engine excessive
wear, "too much fuel,", etc? They never complained about the chip prior to
this. Firestone seems to be trying to cover up something since they didn't
even change the oil as I found out from BMW dealer. BMW dealer said they
couldn't find any fault codes in the car, like it's been erased by Firestone. So
now I asked Firestone to escalate and they're sending a 3rd party someone
to look at the car. BMW dealer said there's nothing they could do to help. I
called BMW corporate customer service and they basically said I'm on my
own since dealers are independently owned and operated. I am not sure if I
have recourse at this time. But I know I never had a problem with engine
prior to this and nothing was ever reported on previous maintenance by
BMW.
Suggestions and input welcome.
Thanks