What would make all 4 injectors stop working

How did you figure out they aren't working? That's very hard to do. Do you have fuel pressure? If not, you have to check for spark too. Don't just stop at the first thing you find missing.

In that case, verify everything else is working by spraying in a little starting fluid or carburetor cleaner. If it runs a few seconds, I would be looking at the anti-theft system. Also, measure the voltage on the dark green / orange wire feeding any injector. There must be full battery voltage there during engine cranking.

Fuel pressure at the rail can be misleading. The fuel pump IS going to run for one second after turning on the ignition switch. If the injectors really aren't firing, the pressure is going to be maintained in the system giving the false impression the pump is running during cranking.

Have you checked for diagnostic fault codes?