It's a common tactic used by scam artists.
This is what SCO did as well in their lawsuit against IBM.
SCO accused IBM, in a public forum, of inappropriately contributing
SCO's copyrighted code to Linux.
The response to the accusation was, of course, "show us the
code".
Even though SCO made their allegations in public, they only agreed
to show the code to a select group of journalists. This was so
their allegations would not have to undergo detailed public
scrutiny.
Ultimately, SCO's allegations were shown to be just smoke and
mirrors. They also faced a lot of backlast from the journalists
that they fooled.
This is the same situation. Basically, Sunshine does not want their
claims to be examined critically.
Sunshine Empire does not want outsiders to be able to rebut their
explanations as they preach to their faithful. I am pretty sure if
they had any evidence at all (eg. signed contracts, etc.) they
would immediately show it as it's essential that they restore
confidence.