The ally encounters should have been checkpointed, or a separate instance, so they don't have to be repeated if you fail, or disconnect, or bug, and Mordremoth should be easier. This fight is such a step up in difficulty, and so twitch dependant it amazes me it was released in the form it's in. It's like they bought in the fractal team to do it. If people want a challenge there are raids and t4 + motes.