not much help but I do know to make rose essential oil it literally takes tons of rose petals to make very little e.o...hence rose oil being so outrageously priced-- I used to work in a herb shop and we kept the rose e.o. locked up because it cost $100+ per 10ml. We used to sell it by the drop!
You could probably make a nice oil infusion by taking a base oil like sweet almond or sunflower and pouring that over a jar filled with petals and leaving it for a few weeks. Sitting it in the sun or gently heating it some other way would speed up the process. (I don't think it would be very strongly scented though-- unless you added some e.o.!) Also rose petals are very tasty added to honey-- again they need some time to impart the flavor but well worth it IMO. Lovely spread on buttered toast! (not if the roses have had chemical treatment tho!)
Zoe, mama to Thomas 01-06