Hi, certainly not an expert, but as noted I had some success with my old Rainbird box. The wiring diagram at the back of my box corresponded to the wiring harness coming from the rainbird and attaching to the multi-strand wire going out to my yard. While the wires to the yard valves/solenoids didn't correspond at all to any pattern, the harness was wired correctly.
I just carefully labeled each wire prior to detaching it from it's zone (The harness wiring was attached to the wires leading out to my yard with wire nuts...looks like you have blue ones in your box). It also looks from your pictures like you have four total zones. There should also be a common wire for a total of five wires. The common wire is the key as even if the zone wires are attached incorrectly, you can easily change them via testing once you've installed your Iro.
I re-attached the common and zone wires to the my Iro and was good to go - the labeling was key.
I hope this helps!