The person talking speaks about an organization called Camarilla.
"Camarilla, on the other hand, suspends judgment entirely...or so goes the party line."
I know that "party line" means "policy" from the following definition I found. The agenda, policy, or ideology of a particular political party. Often used in the plural.(source TFD)
I know that "go" can mean 24. to be phrased, written, or composed: How does that song go?(source TFD)
Does so goes the party line mean "The policy is written that way"