I think he's onto something here!
The fuel pump will run for a few seconds when you first turn the key on to pressurize the system during cranking, but then it needs to see some oil pressure to come back on, that explains the easy start then quick shutdown.
I'd check the connections you can reach or see, especially the ones that got squirted with the hose, both visually & with a wiggle. Maybe take your leaf blower to it, if its moisture related it might dry out.
Check/troubleshoot the fuel pump relay operation and connector, also the oil pressure sending unit wiring. The computer will bypass the the oil pressure signal for a few seconds on start-up but if it doesn't see a reading after that it will shut off the fuel pump relay.
Worth a shot, you may have gotten the connections wet/etc when you cleaned it.