Castle S'nel N'fa, Magickally held fancy chest issue

I've been testing different ways on how to obtain the staff on K'an T'au early and easily for the benefit of unlimited teleportation.

I know the chest can be:
- destroyed with dynamite
- destroyed with a spell like stone throw
- opened by casting disperse magic

What doesn't seem to work however is a scroll of disperse magic.
I also can't attack the chest with my fists despite holding the Alt key.

Any ideas why?

UPDATE: For some bizarre reason, the disperse magic scroll from Liam's workshop doesn't work, but a scroll stolen from Sir Garrick Stout the Captain of the Guard in Dernholm does.

Are there any other places where a scroll of disperse magic can be found? I checked the magic shops in Tarant, Black Root and Ashbury using the inventory hack and none of them seem to sell it.

 

Here is a late answer that is of absolutely no help.

As for your original question, I have no idea. I've only become a Spot Traps master once and I'm not all that fond of teleportation. If I were to hazard a guess as to your second question, I'd say that the scrolls in Liam's workshop are quest items in disguise, seeing as they are there only to close to portal. Try using them to disperse any other sort of magick (or try using the one stolen from Garrick to close to portal) if you want to test my hypothesis; I'm certainly not going to do it.

To your final question, I'm fairly certain that the answer is no. The magick shops in Tarant, Caladon, Ashbury, Blackroot and Quintarra (I believe that's all of them) are more than happy to buy them, but none of them ever have the scrolls in stock. Garrick is also the only character I'm aware of that has the scroll in his inventory, but I've never been actively looking for it so I can't say for sure.

 

The last time I tried to use the disperse magick scroll from Liam's on the portal, I noticed that it didn't work (with a magickal aptitude of one hundred). It's possible that that scroll is simply broken.