Maybe you can try the OBJ format if your object is a pure quadrangles subdivision !
Maybe also decimate...before!

Direct conversion by the native SubD / Creat from File don't work for this case!
or by Import OBJ (by max Smirnov)
and you will have exact quadrangles to nurbs conversion following a %

With the original i am affraid that you can't make something with a such file! :)
here the importOBJ


3dm = 160 megs
zipp = 15 Meg https://moiscript.weebly.com/uploads/3/9/3/8/3938813/bull.zip