You can contact exchange, there are no problem.
I would - even earlier, but they require to fill in some of the tech stuff I am not sure about for RaiB. You on other hand have already setup new nodes/faucet/explorer so you will be able to fill it in - that was the reason I was asking you specifically.
Yes, it's working apparently and I'm setting up more nodes next week.
Excellent news! I think with working network, wallet, faucet and explorer exchange would complete the package - there apparently still is big interest in trading Rais.
I hope original dev understand that community is still here.
if I remember it right, Colin's brother was saying in his "end of development" announcement that they are willing to give up the key for genesis acc. to someone who would continue the development. Have you tried to contact them ? Their emails should be here somewhere or on gith.
Anyway, thanks for supporting RaiB!