step 1: uninstall display link
step2: download legacy driver directly from display link website
https://www.displaylink.com/downloads/file?id=1636 (supports catalina)
restart of course
go to the mpc installer, a green check mark should be beside the install display driver
i tried config screen, "turn display on" that didn't work, however after a reboot and opening the software (still the display didn't work), clicked through the settings... all of a sudden it just popped on...
i also turned screen recording on in security and privacy settings for displaylink
some of these steps might not be necessary, but this is everything i did
im on catalina 10.15.7
hope it works for everyone, i didnt find a solution anywhere else...