This is not tyranny, this is religious cowardice.
The School is PUBLICLY FUNDED.
Yeah, a publicly funded school has to respond to the public, duh. Canada is a pro-gay nation, if you mooch off the taxpayers, you must obey to the taxpayers, the politicians they elect, and the bureaucrats these politicians appoint. Simple as that. The church leader was tested, and he chose government cheese over scripture.
This is no different than borrowing a car from a gay friend and being upset because he will not let you put a Defend Traditional Marriage bumper sticker on it. Even in an 100% orthodox Christian society, a Church institution has no business taking public money, that is how doctrine is corrupted.
And that includes the oh so coveted tax exemption, that also allows some gagging of the pulpit...except in "traditionally black churches", where it is "part of the culture" to speak politics to the congregation. Something about a camel's foot in the door, or a salesman's nose under a tent comes to mind.