The only two things I know of is the Camco lug is heavier gauge and weighs twice as much with better Chrome plate.

The other is that Camco has a spring inside and DW has a plastic stop.

That's great thanks.

Ya really can't tell because it's the same tools making them, til you take one off.

Early DW lugs are very similar to Camco lugs. One of the main differences I've noticed is that the spring in the DW lugs has wider coils, wheras the Camco lugs tend to have tigher coils in the springs.

It also matters which Camco badge the drum has. There were a few variations the turret lug during the George Way and Camco Oaklawn eras. The earlier lugs were made (as far as I remember) by the Consolidated Die Company. If you take the spring out of a lug from this period, you can see the letters CDC on the inside of the lug. Later Camco lugs (certainly by the LA period) do not have this. The LA period lugs and the early DW lugs are very similar.

Another telltale sign is the type of screws used to affix the lugs to the shell. Oaklawn screws have more of a "mushroom" look to them, whereas the early LA screws have wider and flatter heads, and late LA screws are smaller (maybe made of aluminium? would need to check this, but they are different nonetheless).

So there are a lot of nuances, but most Camco and early DW lugs will work cosmetically and are roughly interchangeable. DW later changed the turret lug shape a bit (it is flatter than the Camco design - just hold a newer DW lug side-by-side with a vintage Camco to see the difference), and also moved away from the internal spring, as mentioned previously.

Do you happen to know the badge of your friend's Camco snare?