Need help to fix T-spline generated pipes with self intersected poly-surfaces

Hi Everyone
Im trying to 3d print those two polysurfaces generated directly though T-spline, but turns out found that those polysurfaces are not fully closed and have selfintersection. Couldnt find a way to solve this and i tried mesh and cleaning.
please have a check and help me!
kind regards

also rhino file attached with polysurfaces and meshes version: structure support1.3dm (8.6 MB)

Yeah, those look pretty bad… Here is a new .stl file (not sure if it will upload, ~11Mb) that i have exported and fixed in Magics…

structure (11.2 MB)