You figured it out! That's good !
So for timing if you know we can sync variables too.
-> add instance variable( you will need to sync timer(text object too) to timer (sprite or text) whatever you are using and add one more variable named turnof which should also be instance variable of timer (text)
Then at game start, Host will set timer on and set turnof to 1 means host itself.
After his turn of time up, he will change it to turnof 2 and time to 30 seconds again.
For timing counting you can use timer at host side.
And it is very easy to get time for showing it going down
If you added timer behaviour in Timer (text object) then.
30 - timer.currenttime("turntimer")
( I'm still forgetting something at the end maybe but it's pretty much it. And you'll be having countdown)
And I have to download discord and then only I can add.
I'll add you later on. Right now, just wanna get some sleep😬 I had rough day with using photon in construct 2.
(try above logic and always check if things are going well or not using debugger instead of just assuming)