[Diarmuid doesn't know this man, but he is asking for help and never has Diarmuid been able to resist helping those in need. Especially when he has something in his possession that might very easily offer that assistance.]

I know we have not met before Good Sir, but I was once given some incense that was charmed to provide deep and nightmareless sleep. I do not need to sleep, so have not used it myself. However, if there is a chance it might help you get some of the sleep you seem to so desperately need, I will be more than happy to have it sent to you.

[He might not be able to help with the odd 'memory sharing' abilities the man speaks of, but that doesn't mean he won't help in the ways that he can.]