just a follow up. we ended up having my son get the thimersol free (you need to insist on the single dose application as opposed to the serum drawn from a multi-use vial) and he did not have any increase in tics, thank goodness.
It is difficult to know if the homeopathy is helpful or not because we have made so many other changes (Gluten free, dairy free, lower salicylates, lower oxalates, mostly corn and soy free, and lots of vitamin supplementation based on Great Plans Lab testing and food changes based on ImmunoLabs IgG food sensitivity results. The homeopath does not reveal the remedies by name. However, she (the homeopathy) has been very accurate about some of her predictions (ex, this we cause a brief increase in symptoms followed by period of decrease, or this one will jump start his growth spurt followed by a slight increase in tics and then a low symptom period. She is treating the other behavioral issues as well which she things are inter-connected). So, in general we are definitely continuing with the homeopathy, but can't identify it as the main thing that has helped.
Be sure to find a homeopathy who specializes in children and has treated lots of similar cases before. One person I called initially said she had never treated tics but would be willing to try.