Yes, certainly you can. I believe I mention it. Probably use some kind of regular rose petals as well together with GOOD quality dried ones, which I suggest you soak in some water for a few hours, maybe overnight, in a covered jar.

It all depends on the freshness and actual fragrance of the dried rose petals you have. I would start with a good pinch, about 1/4 cup or so, then after cooking the jam a bit, taste and see if you think it has enough fragrance and if not add more and simmer a bit longer. Difficult for me to give you exact measurements since I do not have at hand the same dried petals you have.