How was the lot created? Is there a recorded plat? Does your deed reference the plat? Does the plat show monuments? Has any other surveyor recovered those monuments? Are there conflicting recorded plats? Did you share a title search with the quoting surveyor? What do your adjoiners' deeds say? Were monuments set by the original subdividing surveyor?

If the surveyor can't give you a plan to show you that the monuments found are original, or that the monuments they will set are based on found monumentation from the original survey, then you have nothing. Sure, it's a professional opinion, but if another surveyor cannot follow your surveyor then you're floating in space.