Thanks, El Corazon

Unfortunately, I don't think it has to do with the USB hub.
I'm powering my entire setup with the Pegasus Astro pocket powerbox advance. (Using the pegasus astro 10A power supply)
The only USB hubs that I use are the one build in to the PPBA and the one in the ASI533.
I did test the hub in the ASI switching the guidecam to the ppba hub or connecting it directly still let to either one or the other camera showing up never both. Also I'm powering the PI4 with the dedicated USB port that Pegasus Astro claims is able to power the PI4.

Next time I setup I will test if powering my PI4 with the 12v. To 5v. Stellarmate cable makes a difference. Just to be sure.

It's good that you've asked but I do indeed define ZWO for both cameras.
The same way it works in my current PI3 setup.

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