The quest is called "Stone Pit" in the game mine called "Stone Quarry" which also has a Side-quest attached to it called "Cave In".
Have you rescued all 10 orphans?
In these types of scenarios it is much more easier to consult, study & follow the maps instead of the videos.
Have you checked out the relevant Wiki pages, quests, maps, videos, guides, walkthroughs & hidden gifts.
You can easily find the solutions to puzzles if you check out the walkthroughs & maps.....everything is clearly & concisely highlighted.... including hidden gifts.
The Wiki pages & this forum will become your best friends throughout your Diggys Adventure journey.
MAP - Stone Quarry
VIDEO - Stone Quarry
Mines, Maps & Videos