96 crank sensor issues

My 96 4.0 auto 4wd got ran with no water
I replaced head, head gasket, radiator.
I had removed the crank sensor, lost one of the weird bolts.
I removed the distributor to reprime the oil system and could never get the engine in time.
I took it to a shop that has all the OB2 diagnostic equip.
They replaced computer, disributer, timing chain.They cleaned the firewall connection ect. it has supposed to have ran and sounded good but shut off
now the crank sensor is not reading
They have supposed to have ied stock mopar sensors and aftermarket. They claim to have turned the engine over moving the sensor in and out with no trigger showing.
I have been with out my XJ too long .
Any ideas welcomed and appreciated.

Just some wild arsed guesses. But check the supply voltage to the CPS and the cam position sensor. My 96 was acting up, it was a short in the 5 volt supply circuit. A partial short (low voltage) in the CPS or the cam position sensor (and other sensors) can have a cross over effect and cause issues in other sensors and lead you down the wrong path.

As a side note my MIL (check engine light) went out, it wouldn't light with the key in the run position. When I unplugged the shorted sensor it came back on again.

Make sure the CPS pigtail is not resting on the exhaust manifold. Check the wiring to your rear O2 sensor.

I don't know but I've been told, having the correct OEM bolt in the CPS is important. just any old bolt won't do.