So what exactly is Scourge beef against VH and what was he trying to achieve on Minos?
Among the usual taunts he has a few interesting lines:
I put them in an order that makes more sense
“The Overseer was wrong about you”
"You are a mockery of our *kind * (??not sure of the last part of this sentence)
“You are a pretender”
“You cannot contain what is loose”
“The Destroyer Cage must be rebuilt”
"I’ve done what the Watcher could not (?? not sure of the last part of this sentence)
From the bit from the dialogue in the trials and those bits I infer that the remnants of Guardians want the VH to take their role of containing the Destroyer and Scourge is not happy about it. Maybe he tried to rebuilt the Destroyer prison (this confirms that the ■■■■ pulled out by Tyreen has long lasting consequences as the Destroyer cannot be killed just contained) by a method akin to how it was originally built by sacrificing the life of numerous beings, in that case the Minos inhabitants (Tanis confirms at the end that they are nowhere to be found they literally disappeared)
Maybe all of this give hints for BL4 and a conflict between Guardians and VH about how to deal with Destroyer threat if they gather humans to sacrifice to build the Destroyer a new prison.