Sweetness looked over the situation for a few moments- as Arkavas moved up to try his luck with the pressure plates, the gnoll gave a soft chuckle and trotted back down the hallway towards the tomb. A few minutes later, she returned with one of the spears that the kenku had been using.
Still chuckling gruffly, Sweetness set to work with the spear and one of her daggers. It was a quick project to notch the haft of the spear deeply enough to set the back of the key into the wood, and to lash the makeshift implement tight with a strip or two of cloth from one of the kenku cloaks.
Smiling a wide, toothy grin, Sweetness reached across the pressure plate portion of the hall with the pole... "Wouldn't try this if I had to pick the lock, yep yep yep," the gnoll barked. "But it ought to work enough to fit the key in and try to give it a turn."
OOC: Is the description of the tool-building clear enough, or do you want a more detailed write-up? The idea, obviously, is to get the key into the key hole and turn it without having to step on the plates. (I'm assuming only a single 5' space is covered by plates)