I'm about 70% sure that I'll be able to help you change the colour of smoke, in at least some of the photos you take.
But that means I'm 30% nervous, of course. If you invest the time and expense, then it turns out that it's not possible after all, you and I will be frustrated and your client will be disappointed.
The decision about whether to try it will have to be up to you.
(I can say, though, that I'm 100% sure that it will be very time-consuming editing. So be sure that you're prepared for that commitment.)