At present, communication between TT and the trilogy modules over II is unidirectional. That is, TT can send data to the other modules, but not receive. We’ve definitely discussed adding bidirectional communication in a future update, but don’t yet have a timeline for when that will be.
Regarding your final suggestion about using MP as the master clock, this should be possible right now. Use the clock output from MP and attach it a TT input. In the corresponding script, you can then send clock signals to ES & WW to keep them all synchronized together. Of course, MP can directly clock WW as well by attaching MP’s clock out to WW’s clock in. The real trick here is in using the II commands to keep ES also synchronized.