It turned out that there were some platforms that were hidden very cleverly and that was the reason why they had not been able to find those platforms for the first time. It was not Rein with his Eye of Truth which managed to find it but it was Stella who found them with her dynamic vision granted by the Eye of Clairvoyance.
At the end it turned out that all four sides had one such hidden platform. Rein and Stella had managed to find them without much trouble so they did not think much about it but Anna and Tasha did not even register the existence of those platforms. That was the reason two unique murals were missing.
After funding the last two pieces of murals, it did not take long for them to solve the puzzle. There were a total of 108 pieces of this mural and the complete picture it was depicting was that of a little girl surrounded by various platforms just like this floor and on each one of the platforms, a monster was standing.