When a colony is ready to hibernate, the vast majority of ants should already be more or less dormant inside the formicarium. Separate the outworld and formicarium, plug both ends, and chill your formicarium. Later, pop the outworld in the fridge for a few minutes and manually relocate any workers to the formicarium. Everyone in both should be sluggish enough to not really put up a fight. If you have so many workers that this is impossible, losing a few probably isn't that big of a deal.
I live in Kansas, so a bit North of you, but I usually only check on them a couple times a month. Make sure nothing is molding, no leaks, temperature holding steady, that sort of thing. Protein won't be necessary, but they might appreciate sugars. I had good results with about three and a half months. Twice during that time, I put them in a cold room, let them more or less wake up, and fed them some sugar water. They were returned to the cooler within a day of that. Is this necessary? Probably not. Will they gladly seize the opportunity? Sure seemed to, and it didn't seem to have any negative effects. People closer to Canada may have different results.
I think the reason you don't find much information is because it's really easy to overthink, but all there really is to it is holding a colony at a set temperature for a few months. It sounds like you're on the right track.
Thanks! You're probably right, and I'm overthinking this... my biggest fear is that I don't get them down long enough (due to warmer winter weather, or that I freeze them trying to do it artificially)... =)
Then have a temp gauge with alarm if gets too cold/hot?
