Ok, I found the solution to my own problem so if someone finds himself on a similar problem there is some documentation here to help them out.
It was right in front of my nose the whole time…
using dansguardian groups, you can create several filters for different groups.
What I ended up doing was putting all the banned sites in ONE bannedsites file and creating different exceptionsitelist files (exceptionsitelistf1, exceptionsitelistf2… you can have upto 99 filters) for each site or group of sites that are allowed for a particular user or user group.
Then simply add each user to a filter on the filtergroup list and you are DONE!
By default all users go to exceptionsitelist (which can be empty and therefore the bannedsitelist applies in full force) and only those users lucky enough to get access granted to sites on the bannedsitelist get the filter2 or filter3… applied to them.
Hope this helps someone,
Best regards to all,