Granite Steps Stained

I have new granite steps. The worker used Sikagard - Natural Look Clear Sealer to brush on the risers. Much of the excess, like water, traveled across the granite steps and stained them, not evenly. He then came back and tried to rid the stains caused by the Sealer and used Miriotic acid to do it. Nothing changed. Then he used Phospheric Acid, again, nothing changed. He then felt if we cover the whole granite slab on each step, maybe the sealer would stain the granite all the same color; but that made the staining worse.

Is there something I can do? The steps were absolutely beautiful until the sealer was splashed onto the risers, and ran across the granite.

Thank you so much!
Bob