My camber was fine (even both sides) before i got some work done to the steering rack.
When i got the car back a had the tracking setup and the camber was uneven . . . . . and like you say, not adjustable.
In my case i knew nothing was bent so after doing some research i found out the camber can be adjusted slightly by unbolting the subframe and moving that.
my camber was -1.24 deg on the drivers side and -0.5 neg on the passenger side.
The movement on the subframe is only slight, but enough to even those figures out. There is basically i little bit of slogger on the bolt holes.
In your case, something might be bent . . . . but i would guess if the figures are similar to mine were, things may have just moved slightly on their bolt holes.