My husband watched several videos (none of which looked like our dryer) and tested the various components that could be bad. The only bad component we found was the ignitor. It was located under the drum, so it was tricky getting it out without taking the entire dryer apart, but a little swearing and a 5/16 ratcheting wrench did the trick. He replaced it and, voila, we have heat again.
We were emboldened to go after the squeak next, but that's another story.