You said he did this mostly when the dogs were playing?

Is it possible he is playing too?

One of my old cats (Lily-bell who came to me as an adult and lived with me 14 years) became less tolerant of noise and random movements as she got older. Kids playing were fine for awhile but after just so long she would go an slap them (she came to me de-clawed). She also would slap the window when neighbors were too noisy too long outside.

Maybe, as my Lily-bell, your older cat demands peace and quiet. Is there a space where the cat can get away from the commtion? Could the dogs be encouraged to play somewhere away from the cat? Lily-bell had the dogs she lived with trained to back down at an evil look... but I would bet she would have disciplined a strange dog if he offended her noise rules....