Moorbridge Treasure Quest

[Borodin]

I'm trying to follow the Quest trail per the Walkthrough, and I've skipped the 2 steps after getting the map (as the Walkthrough suggests), but when I find the proper gravestone and try pressing the lowest button ...nothing happens.
Is this a glitch or do I need to go back and visit the other graves etc.. from walkthru steps 1 & 2. ????

[Fyezall]

Have you tried pressing them all? You're supposed to find a key in one of them, dont know exactly which one. Some release poison, but you'll survive.