In the final battle, Teal'c dispatches a Jaffa by surfacing in the river and he is completely wet. He is never seen wet again in the episode, not even moments later when he saves Carter and Jonas by firing a large weapon to kill another Jaffa.
Coombs pretends to be a Jaffa while wearing his glasses. No Jaffa would ever need glasses as their symbiote would cure their eyesight. He should have been spotted as an imposter immediately.
This episode shows that the Goa'uld ship's brig had access to large air vents that would make escape very easy for prisoners.