First of all, what I can gather from that video is codes P1130, P0170, P0130 and P1555. P0170 and P0130 are related to the O2 sensors. Z18XE has two, one pre-cat in the exhaust manifold and one post-cat in the exhaust, just behind the engine underneath the car. They run two sensors as the second one is to verify that the catalytic converter is present and functioning. P1130 is saying the front O2 is registering a signal that is outside the ECU's range. To me, that's sounding like a duff O2 sensor or the wiring in relation to it. Usually happens if the exhaust has been modified or some cheap Chinese sensors (personally I'd use genuine or a well known brand like NTK where possible).

P1555. This one is common to the Z18 engine and very easy to fix. Take the throttle body off the engine and use some carby cleaner with a rag or brush to thoroughly clean the barrel of the throttle body and the edges of the butterfly. Because they're drive by wire throttles, they're opened slightly at idle by the ECU to control idle speed. What happens is the gunk that ends up caked around the edges of the butterfly closes up some of that gap and the throttle body has to compensate by opening the throttle more. As a result, the throttle position sensor gives the ECU a reading higher than it expects and it then triggers the code. But as I said, very easy to fix and costs almost nothing. Can even do it without taking the throttle body off, but it's much easier taking it off.

As for Z18XEs having EGR valves, they do have them, but just not on the Astra variants. The XC Barina/Corsa C SRi has pretty much the same Z18 engine, but with an EGR valve up until around mid 2004. Somewhere along the line, Opel realised the EGR valves were pointless on petrol engines and did stuff all to improve emissions, not to mention, somewhat troublesome.