Is it safe for him (93) to take more than one pill at the same time?

NO. Ask your pharmacist what order they should be taken in and how far apart.

If he can swallow more than one at a time that's wonderful!! So many have trouble swallowing pills one at a time they must take them with something like applesauce, some people even have to have them crushed. When my mom was in the nursing home for respite care the nurse administering her meds tried to give her all of them in one spoon of applesauce (this for a woman known to have swallowing difficulties!), so it must be a common practice there.