Well, this particular camera does not invest me with experience. I do not think that I ever even handled one.
However, wobble can be caused by, probably, one of two things. First, open the back and look at the rear part of the lens. Does it have a ring around it? Usually, with RFs of this type, the lens component is held onto the body with a threaded ring (that might now be loose).
Another possibility would be to remove the front logo ring (should unscrew) and dive into the innards without being too 'distructive'. There just might be some screws loose which could easily be tightened. I have a feeling that this problem might not be too difficult, but I do not want to impart any guarantees here. As you look, both intently and gently, wobble the lens to try to determine just what is loose.
The Petri RFs seem to be plagued with this 'wobble'. - David Lyga