Try to keep the heat down a little, but you have good air movement, and that makes a big difference.
I usually hang a thermo from a link chain.....of course it has to be COMPLETELY sealed and secure, meaning all wires policed, no chance of shorts or fire....but this allows the thermo to be lifted or lowered to the height of the canopy. ONLY DO THIS IF YOU CAN DO IT SAFE.
I have also setup thermos and humidies on a board....again secure and safe.....then set up 3 or 4 mounting spots up the wall. When the plants hit spot 2....move it up to spot 3.
Just a couple ideas I have tried before.
That being said....you should be fine. MJ is hardy, and your plants specifically look very durable. Try not to let it happen too often, but you will be fine.
Just imagine a plant in a desolate outdoor location, full sun at the peak of summer. 90 is not too bad.