I have built a test image that includes DVSwitch Server and AllStar. This is a Raspbian Buster with the current kernel. You do not need to pin the kernel or headers.
To setup DVSwitch Server type dvs
To setup AllStar type asl-menu

The image is in the zip file at <http://dvswitch.org/files/DVSwitch_Images/Raspberry_Pi/Buster/2021-02-14-DVSwitch-Server-AllStar-lite.zip>