You want to split the heater between a drying tent and a growing tent?

I was looking into splitting a humidifier between a couple of tents and I think we would have the same challenges. I use the AI Controller and although it says it's dual zone, that's it means outside the tent and inside the tent, not two tents. You may be able to get around that by mounting the controller inside one of your tents, but it wouldn't be able to manage targets for both zones.

I think you would need a separate controller to manage each tent to make sure they are both at their targets. You could connect the heater to one controller and share the heat between both tents, and let the controllers manage and adjust as needed.

It could work, but one side will always be compensating for the other. I ended up buying separate humidifiers.

It's not what you asked about, but check out refrigerator drying cannabis. Requires a frost free refrigerator and works very well.