'Clang'! 'clang'! Certain that the guards Could hear the racket if Xanths continues with his current barage, reconciders using his dagger, and finds that it's keen edge easily scratches away the newly formed seal.
An hour latter, he had worked as much free as he could with the dagger, and the guards seem oblivious to the activities. It's now about 10 am (16 hours since the meeting at the inn had started). Some of you are feeling the lack of sleep, and took shifts to nap while Xanths worked.
Xanths, finishing finally, placed his dagger (which is only slightly mared, nothing an hour with a whet stone won't fix)back in it's sheath and grabbed the grate. He notes that it was placed from the inside, though the lock was on the outside. He pulls inward with all of his strength, and feels it budge slightly. Getting the orcs and Darhaan's help, the two successfully rip it from it's moores, the way out now available.