This does work and returns the coordinates of the vertex:
This is all executed on Rhino 6
But I have to go get the whole array just for 1 vertex:
import rhinoscriptsyntax as rs
import Rhino
def test():
MeshID = rs.GetObject("Pick a Mesh")
Mesh = rs.coercemesh(MeshID)
VerticesList = Mesh.Vertices
VerticesListCoordinates = Rhino.Geometry.Collections.MeshVertexList.ToPoint3dArray(VerticesList)
print VerticesListCoordinates[1]
test()