Turn Off Assistive Touch Menu Button WITHOUT Turning Assistive Touch OFF

OK, please do not send me an automated text telling me how to turn off Assistive Touch, I need it to stay ON because of my Bluetooth Mouse needing the third button to be assigned. Everything works fine with the mouse, but that annoying box with the white box keeps popping up. I NEVER use it and I don’t want to see it again. Please help me turn off this button so it never appears on my screen again. Thanks in advance.

If I cannot accomplish the above, please point me to a Bluetooth Mouse with its own assign software for the iPad.