It reminds me of an issue I've had on my Smith and Wesson model 681 .357, which is from the 1980's. I should start by saying that S&W issued a recall on this and other similar L framed revolvers about 30 years ago. The problem was that people were having the primers deform from the way the firing pin struck the primers, and this would bind up the action a bit. Since my gun had spent most of it's life as a police issue gun from Australia, it was never sent back for the recall (due to the long distance, I presume.) And since I never experienced any problems with .38 or standard load .357's, I never bothered sending it back, either.
But when I shot some hotter "heavy" .357 loads from Buffalo Bore last year, I experienced the same symptoms your friend describes, which also happens to be what Smith and Wesson describes as the classic primer deformation symptom of their L frame revolvers from the '80's. So I sent it back for the recall. They sent it back to me, but I'm not exactly sure what they did to the gun...something with the firing pin and recoil shield around the area of the firing pin, it seems. Problem is, even after sending it in, I still get some of the same issues with Buffalo Bore heavy loads. I'm going to try Grizzly heavy ammo, and see what happens. If it doesn't have a problem with the Griz brand, I'll forget about it and use Griz. But the gun's main purpose is as large predator defense when we're in the Rockies, so if the gun doesn't work with ANY heavy loads, it'll have to go back again. ANYWAY....
...BACK TO YOUR GUN. Hopefully your friend saved the spent brass from his shooting session...but I'm not counting on it. Looking at the primers would be the big clue. With my 681, you can really tell...the spent Buffalo Bore casings have primers that are bulged out enough so that they don't sit flush on the table when you stand them on end. Some say the Smith and Wesson recall problem was only an issue with certain brands of ammo or primers. This might be the case, as many other brands have worked fine, which sounds like the case with your Rossi. It's hard to say if the problem is only a primer issue or a heavy load issue until you try an assortment of ammo. Reloads could be heavy loads and/or use the wrong kind of (too soft) primer.
If the problem is specific only to a small assortment of ammo brands, I'd say don't try and "fix" the gun, but just use the best working brand of ammo. I will say this: eastern European ammo brands have generally harder primers - Herters, S&B and many others - so I'm guessing there generally won't be issues with that stuff, if you can find it. The harder primers on this ammo has definitely eliminated issues I've had on other guns that have assorted issues related to soft primers.