Yes, I see...

Well, I was mainly thinking that they (Morgoth and Snaga) were both scared by the other, and could not withstand the other's presence... did not dare to go to the other's presence... (in Morgoth's case, kind of indirectly) I actually thought about some other reason but now I seem to have forgotten it

...in any case, when you speak about Sam, there could be hardly anyone else than Snaga in such connection.