Hong Kong and Macau - Group Ticket for YYZ-HKG-YYZ

First, I'm sorry if I put this in the wrong forum, because it's not airline specific.

I'm looking to book tickets for YYZ-HKG-YYZ for a big group of people (20+) for travel near the end of June. Does anybody know if any airline has discount for group fares, and if yes, how much is the typical discount I can expect?

Most online booking websites only allow up to 9 tickets and the price is no different from the regular fare :(

Call a travel agent. Chinatown travel agents would give me tiny discounts(which is understandable as there is very little margin) when buying 4 or 5.

Get a Toronto Chinese Newspaper and go the the travel agent advertising pages and start calling.
The margin is very tiny for discounted Y so set your expectation low. However the big savings is C/J tickets.

The normal airline discount is about 5% for large groups. (for every 15 passengers, a "tour guide" ticket is sometimes gratis)

The normal airline discount is about 5% for large groups. (for every 15 passengers, a "tour guide" ticket is sometimes gratis)

Can you please refer us to the airline or travel agency that will do this for deeply discounted YYZ HKG YYZ route?