Completed it, defeated the bosses (regular mode), saw loot, clicked on Next hoping for dialogue and was sent back to the map and it shows as incomplete. Turns out the loot isn’t showing in activity log but I cannot be certain there was anything of sufficient value in it.
I know it was this stage as I had to wait for WE to charge and it is all the blue monsters with mana on all mob waves.
There was no connection error, it was seemless.
Not looking for recompense, just letting you know.