each group would need to start SAS with something distinctive.
If the client userID is available, you could use that to determine the "group".
If that is not available, you could have each group address its own connection, and have each "connection" use a customised command to start or spawn a SAS session.
When starting SAS, more than one config file can be defined. That allows normal "installation definition" options to be in a main config while special parameter/options are in a small "override" config file.
If SAS is started with a command in which no config is defined, you have the best of both worlds! The config file in the sas.exe folder, as well as a SASv9.cfg in the "current folder" will be used.