Here is the problem with your setup:
– If you set the H9 to midi thru it wil not send midi clock. Think of midi-thru as a “read-only” setting. Then this is what you need because you also want to pass thru (to the next H9) the information received from the GCP.
– If you set the H9 to “Transmit” it will transmit the midi clock, but will not pass (block) the received midi from the GCP
Do you see the problem ? 
You then have a few ways to solve this:
You can use a switch on the GCP for tap-tempo. Configure all the H9 as midi-thru and set “Midi settings” -> “Assign midi CC message to pedal function” -> “tap tempo” to the same CC you are sending from the GCP for the tap tempo (make sure it is momentary).
You can also use a midi merger/splitter (from midi-solution OR the m-audio midi sport 2×2 anniversary ed). There is an excellent post about this there:
https://www.eventideaudio.com/community/forum/stompboxes/ultimate-ptmfactor-control-musicomlab-mkiii
The best way to do this is shown on post #23
-You don’t need a merger and a splitter, just one box: the m-audio midisport 2×2 anniversary ed (has to be anniversary edition, the 4×4 will not work))
-The midi controller is your GCP
-The Factor pedals are your H9s
LA
