survelliance, inside . . .
methinks is highly unlikely. The headaches to get authority to do a sneak and peek and place cameras would be amazing considering the suspected criminal activity. The survelliance was likely from the outside of the building identifying patrons, employees, etc. I also strongly suspect any evidence of criminal activity in any particular case will come from one of the people involved.
It is possible, but unlikely, that the shop had a camera system and leo found tapes or such.
If you are on the list, 2 words, 5th Amendment. Remember, nobody talks, everybody walks.
Nemo