I went around and around with trying to get install.sh to work correctly on a 4b running buster. What eventually worked was installing docker and docker-compose using these instructions https://dev.to/rohansawant/installing-docker-and-docker-compose-on-the-raspberry-pi-in-5-simple-steps-3mgl and then following that up with manually running install.sh functions manually starting at line 138 "build_containers"
I went around and around with trying to get install.sh to work correctly on a 4b running buster. What eventually worked was installing docker and docker-compose using these instructions https://dev.to/rohansawant/installing-docker-and-docker-compose-on-the-raspberry-pi-in-5-simple-steps-3mgl and then following that up with manually running install.sh functions manually starting at line 138 "build_containers"