Well the literature I have read includes a great many things, though most of them have some sort of biological basis, and exhibit a phenomenal ability to function with lost mass. Such as by regenerating or using some sort of magical means of direct locomotion, akin to specialised telekinesis. I propose, therefore, that rather than destroying the flesh, we should place something in its place that is not functional.
Prom-G.S.20-00 "Lodestone" shotgun
This 20mm 5-round overhead-clip pump-action shotgun is loaded with specialised shells that act to harden animal flesh. They contain a mix of pellets:
Depleted Uranium for penetration
Coagulants to solidify blood
Dessicants to reduce fluid content
Whatever we can find to stiffen fat, skin, and cartelege. Looking largely at enzymes and toxins.
The intent here is that even if the werewolf can only suffer permanent harm from silver bullets, if its shoulder turns into an immobile lump then it can buy our squad time to bring out speciality weapons or flee the scene before the critter can deal with it. given that the blood-flow is stopped, there shouldn't be much that can remove the area with subtelty, forcing them to rip out the affected area if they want to resolve the problem more quickly than waiting for it to be dissolved by their natural processes.
Fire should work against the minor beasties, but loads of things from the more mystical bent are completely immune. Dragons are an obvious example, but even humble salamanders(Everyone knows that if you set fire to a log and a lizard runs out, it is because the fire created a lizard!) could be weaponised. Not to mention the likes of banshees. But anyone with frost magic could swat it away and even a wereworlf will probably just regenerate through the burn and attack through the pain with its signature ferocity. Even a zombie ought to be an issue in flammable regions, what with it turning from a shambling corpse into a shambling fire for the half-minute it takes for its insides to harden. And what if it was not a zombie, but actually a skeleton that still had its flesh attached! Then it just waits for the flesh to fall off and charges again, unless we are talking really intense flames, at which point we are back to the close-quarters issue, and some supers are going to be stealthy and/or swift enough to get close...