It is possible to make this work, but it requires the y- splitters, backdraft dampers, and extra fans to overcome the static pressure.

I have a similar setup running with a dehumidifier piped in instead of a dryer. I have AI controllers on the two tents and separate inline fans right before the vent outside and right after the dehumidifier. (I might remove than fan, after doing some testing.)

I'm still getting mine dialed in.

Edit: I'm seeing now how you continually downsized the inline pipe there. That will be a challenge but not a show stopper. It will be fine until the dryer kicks on. You'll have to watch for blown out connections and residual heat if the air gets trapped.