My cats won't eat more than 1/4 of a can of fancy feast at a time

I would really like to feed my cats a mostly wet food diet, especially because one of them has some dental issues that makes eating dry food difficult. The only wet food that I've found that they will eat every day is watered down fancy feast. I have 5 cats, and I feed them breakfast and dinner by mixing one can of fancy feast pate mixed with one can of savory centers fancy feast and one can of water. That mixture gets split between all 5 cats, so each cat is getting a little less than half a can mixed with water (twice a day.) The water is necessary because they don't like the texture without it. Without the water, they just lick the food without actually eating it.

Two of my cats won't eat more than half their plate, so that's only like 1/4 of a can. I am worried about their calorie intake, because they will barely eat their kibble either (each cat gets 1/3 cup Purina Pro Plan for lunch in RFID feeders which they only eat about half of). One of these cats is 9lbs and the other is 12lbs.

I would prefer to feed them mostly wet food but how can I when they won't eat enough calories? They refuse to eat food that has been refrigerated. There is so much confusing and contradicting information on calorie intake for cats that I don't even know if I'm feeding them correctly or if they are being malnourished. What else can I do?