Can anybody help me figure out if I'm missing hardware or having a more fun problem.

I have an OBDXpro VT that easily connects to my 04 tahoe. I thought it could also read my Monte PCM, but PCM hammer attempts to get the VIN and times out.

Is this hardware even compatible? I used to use a DHP 10 years ago, but I no longer have the hardware.

Can somebody hold my hand a bit?

If it should connect, I'm wondering if I have a BCM issue, but an ELM can read out data to my phone. I don't have cruise control and my power door locks don't unlock, but they will lock. Not sure if it's BCM caused or other issues. I just bought the car 3 days ago.