I have a Honda 3000 watt RV generator and it has a fuel shut off and a float bowl drain. So if you shut off the fuel shut off and drain the bowl the only place there is fuel is in the tank and the lines to the shut-off.
Watched your video, you did a great repair. I looked at my Jayco Eagle 5th Wheel which is a 2006 model and was worried on what I might find but it's like new. It is constructed similarly to your 5th Wheel. Just wondering if there was another reason that this section failed?