What questions do we want to ask?
How big is the disk anyway?
The size of the disk is consistent with tidal truncation.
Does the rim expand vertically due to the impact?
Yes, H/R approximately 1/6 -
but
is column density large enough?
Does the impact drive a shock wave into the disk?
Yes,
but
is it the overflowing stream that drives the shock, and does the shock continue in past the stream?
Does the disk accrete?!
Yes!
But
what about radii smaller than point of closest approach?
Does the stream flow over/under the disk?
Yes. Most of the mass goes over/under disk,
but
what about more realistic EOS?
If so, where and how does it merge, is there a splash?
Stream merges at point of closest approach for ballistic trajectory