﴿ فَوَقَعَ ٱلْحَقُّ وَبَطَلَ مَا كَانُوا۟ يَعْمَلُونَ ﴾

“whereupon the truth was established, and vain was proved all that they had been doing.”

(Thus was the Truth vindicated) it became clear that Moses was right (and that which they were doing) of sorcery (was made vain) fizzled away.