the rocker arms seems like they have been recently buffed clean by a mechanic or someone, the flush you poured in will not remove this varnish deposit coated on the outside - it will only clean out the oil pressure galleries and drain galleries slightly.
To clean this varnish deposit - you need to use a full synthetic oil in it or diesel engine oil in it and it will become clean as new after a few oil changes.
make sure the PCV valve is clean and the breather line on the air filter is also clean, make sure the engine gets hot (ensure thermostat valve is in place) - oil needs to get hot to clean the engine.