Will not start after getting stuck in the mud?

This is my friend's car but yesterday she had parked in a spot at her sister's house that she didn't know was muddy and got stuck. She left in another vehicle and when she came back, her brother-in-law was flooring the gas pedal and had the RPMs rapped out, trying to get it unstuck. She said he got it unstuck but he'd been rapping it out and there was smoke coming from the vehicle. Now I'm not sure if the smoke was from under the hood or the wheels but after this, the vehicle lost power and now will not start. Checked fuses, oil, even changed the alternator since mechanic friend thought that was the issue but that didn't fix it. Fluids are good, there's power, just doesn't turn over and start. They cannot see any visible issue. Any ideas what the issue could be or where to look?