just tried this (shortcut to boss, not the -requestgmhelp-stuck) and I think they have added more invisible walls to block this route.
The spot at 1:00 in the first video, I was never able to get to the top, there now seems to be something blocking, I get to the last spot before the top but can't get to the top.
I ended up pulling individual mobs and killing them and walking along the path to the 2nd checkpoint fire. This ended up being much easier than I thought.
As for the part at 1:53 in the first video, I was able to get here, but, no matter how many times I jumped and teleported I wasn't able to get to the next step. But, I solved this by just running around that next corner avoiding the mobs, they path, and I waited until they were to the right and ran by them. I've done this several times, sometime I get mobs, sometimes I don't. When I do it's only the smaller easy to kill guys, which I was able to deal with.
As for Pyraphenia, it looks like she resets now if you run out to your spot. To solve this I single pulled the small guys on the right and killed them, then jumped up the rocks on the right to the point where there's a long point at the top (sorry don't have an image), I was able to pull there but the adds at 66% and 33% were able to hit me, I found if I back down the point a little and to the right I was able to kill Pyraphenia without issue. She never tried to get close to me, she just stood there letting me attack, same with the adds, it's like they couldn't see me.
Anyway, just wanted to let you know about my experience. I may try again and if I do I'll post an image of what I mean on that last part.
One question, is there an easier way to get there without having to run the entire length of the zone to enter as non-epic?