Sorry, but they can DO whatever they want to DO and SEEK whatever they want to SEEK.
What matters is how you respond to it and defend against it.
And, apparently, you haven't done so well in that department if they are still living there without paying rent.
Did you file a response to the OSC giving grounds why it shouldn't be granted? Did you ask for a hearing?
If you didn't, that's why they got it granted.
I suggest you avail yourself of the services of an attorney or this is likely to drag out for another 4 months or more.
Seems like you are faced with professional deadbeats that know how to work both the system and unknowledgeable landlords.