AAS contacted Vancouver Coastal Health which now handles what the old Vancouver Health Department used to handle. An agent went and looked and found that the "cage" that was described was chicken wire that was intended to keep pigeons from roosting under the market's awning.
The pigeons weren't, as the phone message sounded, being caged for the live-bird meat market. The wiring was imperfect and pigeons were getting inside it. The owner was instructed to make the wiring pigeon-proof or take it down entirely.
Thank you to those who offered to go take photos.