Be aware that most elderly patients are incontinent to some extent often wearing adult diapers and that the smell of urine/feces on patients may make him curious to sniff in those places. That may startle or frighten the patient. Old people fall easily trying to take a step back. It might be wise to having greetings with sitting patients until you get a good sense of how Midnite is going to react in this new environment.
It's a good thing you will be doing. My Grandmother-in-law and the residents at the nursing home she is at love it when my MIL brings in her lap dog to visit. He's small so it's easy with him to be put in someone's lap for visits.
Good luck to you and let us know how it goes.