With the growth in this area in the past few years, I think that they might see it as too big an exposure to lose.
From a
star article in 2013:
"Records show the building was purchased for $2 from a contractor called Plaza Investment Co. in 1979."
Meaning, they probably convinced a scientologist churchgoer to fork over a property they owned for peanuts. Any money they make (and it's obvious they haven't spent a whole lot in renovation or repair since '79) less taxes is likely to be pure profit.
I don't see any way that they can get back in there, or any logical reason for them to avoid selling and funnel that money back into the church. They likely left due to safety concerns or the costs of just running it. Church income is shrinking and yet, despite the potential money, they haven't yet and are not going to sell. They've planned this location to be one of their "Ideal Orgs" (scientology for "flagship location"). They want to hold onto it. The CBC
reported last year that their Montreal La Patrie Building location (also intended as an Ideal Org) was on the brink of being seized for failure to pay back taxes. And there was a similar pattern of getting permits and not following through with regards to property standards. That building is also vacant. I can't find anything recent about whether they've paid the arrears, but it's doubtful. They very much don't "believe" that the government is legitimate, which is probably why they didn't bother paying the taxes in the first place. I tend to believe they'd find a legal stay of execution, rather than a monetary one.
From all I've seen or read about the CoS, logic and common sense aren't two things they hold dearly. I think they're likely holding out hope that they can rope in a whale who'll pay all their problems away. But in a "religion" that less than 1800 people in the entire country declare on the 2016 census, they're not likely to find the money anytime soon.
To add: They also fund the renovation of their Ideal Orgs strictly using churchgoer donations. The church itself isn't likely to sink money from their coffers into it. They want a parishioner to pay for it.