At the invisible wall, where I used blink to get through it, You can use AUTOUNSTUCK to get through it. Just remember to have your HS on CD or just destroy it.
Short video showing exploited way to the Sunwell and M'uru's room. Done on Kor'gall Eu. /who window open to prove live realmness.
I found the blinking spot accidentally in our raid. After the raid I tried if i could jump over the wall and it worked! I wondered around the Island for about 2 hours after I accidentally found the "not so solid wall" and got under the whole area.
After that I started looking for a way to the Sunwell which took me about 30 minutes.
Finding the way to M'uru's room was much easier; just saw the high point next to Magister's Terrace and slow falled on the platform just before M'uru.
Then I tried if I could use auto-unstuck to get through the invisible wall where I used blink and that worked too!