Problem with the last secret in "Down in a Hole"

[NICKTIM]

I've made this level 3 times, it's supposed that the last secret is under the excavator after activating it, but it doesn't appear, i've played the level 4 or 5 times, i don't know if I'm forgeting something or it's a bug?

[inovade]

oh that, see the box where you make jumps?
put it besides the boulder to be destroyed

once you've operate it, both of them should be destroyed and there it is
most text guide are ♥♥♥♥, better use video alongside it