Okay, I tried going the other way with the voltage dividers.

Instead of the prior 4.7k/10k which would have resulted in 2.25v from a 3.3v input, I tried 10k/10k which results in 1.65v from a 3.3v input.

This seems to be working now on the test bench, without the crackling. Next, to test a true cold boot. First, chill then put on the test bench, then, put in the car overnight and see how it does in the morning.

Crossing fingers!