Hi @Pamela202, I don't think that hosting a deaf couple can give a lot of trouble unless you want to chat with them. I don't know what "materials to communicate" would had you prepared. A notebook to write there and show them? That's rude.
For my experience deaf people that travel are perfectly used to not-deaf people. Think of them as Chinese that doesn't speak a bit of English. What you do with non English speakers? Mimics. So that's the same case.
As I said if they didn't cause you trouble because of their dissability I don't believe you should mention it. Were they nice? Left the place clean and tidy? Did they follow the house rules?
I would have been more worried if they were a couple in wheelchairs as your home perhaps is not prepared for those, but deaf people are completly functional and don't need anything especial.