Gothmogs and dragons and noobs, oh my

[Raynor]

beasts inhabited by dreadful spirits that he had imprisoned in their bodies.

I would say it is more likely that he imprisoned them in their original bodies, rather than he 'put' them there.

And these spirits had to be at least somewhat sentient, since Draugluin spoke, though only once.

In Myths Transformed, Tolkien speculated that orcs, who at the time he considered that they had no fea, were reeling off 'records' of language set in them. Also, Draugluin words aren't that much sophisticated. I would say even a modern day dog can be trained to give signals of various enemies.