I love the reporting here.... no actual details, but talk about "toxic" refrigerant. Unless they used Ammonia, the word toxic should not be used. Pure Nitrogen can suffocate people... everyone now has to panic after learning there is nitrogen in the air!
how can the leak be in multiple units? Sounds like some sort of VRF system and I see one unit being affected since the entire system can discharge in one unit. But multiple? After the first significant leak, there isn't enough refrigerant left and they would have noticed lack of cooling performance.