IF the AC unit is running and then leaking onto the roof then it is possible you are seeing the water getting inside the RV. Your AC unit should have drip cups that collect the condensation when it is running, they sit under the AC unit, when they fill up they leak onto the roof and the water should run off the roof to the ground. IF they were cracked the water might pool up inside the AC unit and then be able to get in. On your AC unit you will have a gasket that is between the roof ac and roof, if you pull the interior cover off you should see 4 or 5 very large bolts running into the AC unit, make sure they are snug, they can vibrate loose over time to the point you can spin them with your fingers. IF they are loose snug them up and put about 4 turns on each one, there is a torque spec of about 12" lbs, not ft lbs, so it is not that much.
Inspect the roof really good as well, look for any cracks or voids if you see any I would use Dicor sealant most RV shops carry that. You can also pull some screws above the areas you are getting water into and see if they are rusty, that would be a red flag, put a little clear silicone in the holes and put the screws back in.
Hope this points you in the right direction, if you have more questions or concerns please feel free to contact me, follow ups are included, I am around daily and respond when I can....
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