Sorry for the new post, but I could not post to the original one.
I recently got the JG Maker Artist-D IDEX printer and it has the Back-Powering issue. I really did not want to tape over the 5vdc, and I did not want to use a USB extender cable and break the 5vdc connection there.
I decided to try just hooking up a USB Hub to my Pi, and just connecting my printer to it that way. as it turns out, just put a USB Hub in-between the printer and the pi and problem solved. I can not provide a link for the one I used as it is not on Amazon anymore, but it one that you hook up a PD to and it supplies the devices with power. I just did not hook up the power to it as there was not need.
I did not see anything about this method, and my printer was not listed, so I thought I would provide to the cause. I also started contributing to you via patron.
Artist-D IDEX 3D Printer Dual Independent Extruder
hope this helps,
Jason