REALLY? BROKEN FLYWHEEL?

This is a non-mopar but it's mainly a rant anyway: I have a 2008 Ford Ranger with a 4 cyl. w/Automatic 5 OD. 248,000 miles. Transmission went out, lost 3 forward gears and reverse.
I don't have the time to work on it so I took it to the most well known tranny shop in the country. Paid out the *** for rebuilt trans and converter. 30 days it's leaking and slipping, they fix the leak but still missed a gear now and then, so brought it back and they replaced the trans and converter under warranty. Two months later about 5,000 miles, (I drive 100 miles a day) I hear a noise that sounds like an exhaust leak followed by a complete loss of forward motion while at speed. Engine still running but trans just spinning. Tow in to trans shop and the diagnosis is a broken flywheel from "normal wear and tear". I knew the flywheel or somthing had broken, but I feel it has to do with the rebuilt trans or the installation. What do you guys think? Thanks in advance for your input
With 248,000 miles on the car, one would think that the re-and-re guys would look at it. As a matter of fact, with that number of miles on it, to me, the service adviser should have told his guys to inspect it. Stuff does wear out. It should have been inspected the first time the transmission was out.