His best scopes, even if they show a small FOV (15-45') and poor ep. are of
excellent quality for the time.
Galileo wasn't able to make sense of Saturn. But he may have had in the
back of his mind that all objects in the sky are spheres, and tried his
best to reconcile that with what he saw of Saturn. The image size must
have been pretty small, and any issues with the scope probably made
things even harder to figure out. He thought Saturn was 3 spheres in a
row. But those side spheres varied in size over the years. I think he
just left it as an unsolved mystery to be solved later rather than
declare something as solid fact.