Fuel goes into the IP's thru the rubber hoses. You can remove one and see if fuel squirts out when the fuel pump is running.
If so then reattach the hose and then loosen the hard line on top of the IP. Turn the set over with S1 and see if fuel weeps out when attempting to start it.
If you got fuel at the rubber hose but not from the hard line then you may have a stuck fuel rack. If it's stuck in the STOP position it won't allow the IP's to pump any fuel.
You can check that by removing the plug on the governor body. Shown below.
Once removed you can spot the end of the fuel rack to the right in the opening.
See if that moves out of sight when you manually rotate the lever on the side of the governor that the fuel solenoid moves when cranking.
If it doesn't you may want to give it a nudge while holding the solenoid in the run position to see if it's stuck and can get it to move.
View attachment 885211