Absolutely.
I dust silkworms with calcium w/out D3 since they grab on to quite a bit of the supplement.
Just tap part of the worm in the powder.
The idea that you shouldn't use a supplement with silkworms or hornworms because they have a higher calcium to phosphorous ratio seems silly to me.
Are you sure your chameleon is digesting those?
In my opinion, if you are supplementing that day ... you dust whatever you are feeding with whatever you are supplementing with.
I dust with calcium once a day (the morning feeding) regardless of what the feeder is, PLUS every time I offer crickets. So up to twice a day. I do not dust every insect in every meal.