The Ontario Fish and Wildlife Conservation Act says A) you need a license to hunt, and B) defines hunting as: "lying in wait for, searching for, being on the trail of, pursuing, chasing or shooting at wildlife," and to paraphrase, it doesn't matter who eventually kills the animal, or if the animal was even killed, so long as there was intent to kill it.
The general consensus is that to participate in the hunt in any way, he must be licensed. The case law on the issue is limited, but generally you need a license to hunt, and hunting in any way is interpreted broadly to include deploying decoys, managing calls, scouting, etc. Anything that aids the guy with the gun is generally considered to also be hunting.
If a CO finds him holding a pair of binos scouting the tree line, then he is hunting and is in trouble if he doesn't have a license. If your brother is completely not doing anything hunting related then you MIGHT be fine. Even if he could register for a hunter safety course that takes place afterwards, you would have something to offer the CO that demonstrates your intent to comply with the law. That's often good enough, but thats you begging for discretion.
Other provinces are more lenient, but in Ontario, they are pretty clear that if you are going on a hunting trip, sitting in a blind, looking out for animals etc, You need a license.