1. Turn the first statue's disc 3 times.
2. Go down the stairs and trigger the Grubber cutscene.
3. When the Grubber walks away get out of hiding and take a left.
4. Turn the second statue's disc 1 time.
5. Go back to your original hiding place and wait for the Grubber to return.
6. When the Grubber has walk past you take the right passage.
7. Turn the third statue's disc 3 times.
8. Walk further into the passage and collapse the broken wall.
9. Go up the stairs. Turn right until you reach the first tunnel on the left hand side which containing the last statue.
10. Turn the disc 3 times.
11. Go back to the tunnel you came from and continue forwards until you come to the room with the sarcophagus
12. After you've picked up the egg go back the way you came.
13. Place the egg on the gate in the room April fell into.
I've done it this way since my second playthrough and I haven't had a problem with this area since. Hope the same will be true for the people reading this.