I'm in the Industrial Era right now and in a bit of a pickle.  My hand got forced and i had to assimilate an Independent People's city before my rivals could because it would have shifted the balance of power in their favor had i not done so.

The problem is that it resulted in a rather harsh penalty to my influence (-870!) because i am now 4 cities above the cap.  Getting the Space Orbital Technology in the Contemporary Era to fix this is going to take way too long so i was hoping for The Combine Event: https://humankind.fandom.com/wiki/The_Combine to trigger which would raise the cap by one if i pick the right choice.

Unfortunately it does not seem to want to pop up, i've had every possible Event happen except that specific one.  Can someone tell me if there are conditions for it to trigger or if it is completely random?  Because i cannot stay forever in the Industrial Era hoping i'll get lucky, my rival Empires aren't twiddling their thumbs in the meantime and are starting to catch up to me.

Sorry, I don't know how to trigger the event. If you have influence stockpiled merge some cities. If not, you can ransack the new city center, build outpost after and attach later when you can.