Welcome to the forum its a great place to get your questions answered. Myself I could only provide you an educated guess as to the actual position I will leave that to other forum members who will have the answer.
Jake my sidekick (yellow Lab)
2017 RAM 2500 CC 4X4 Cummins Diesel
2016 Flagstaff 26 FKWS
AF&AM & El Korah Shrine of Idaho
Electrical engineer here. You definitely need a transfer switch if you are installing a gen unless you want to kill someone and cause a lot of damage. If your RV has a generator prep package there will be one installed along with cables pulled into the generator compartment. In my 29HFS it is located in a compartment under the bed.
If you do not have a transfer switch don't install the generator without one. That switch isolates the generator power from the incoming shore power.
Some motor homes with generators do not have a transfer switch. The generator output goes to a 30 amp outlet in the wire storage compartment. If you want to use the generator you just plug the shore power cord into that outlet and you start the generator.
It is recommended also to plug the shore power cord into the generator outlet anytime it is not plugged in to shore power. That way if you want to remote start the generator you can do that and have generator power without stopping or getting out of the MH. This of course is if you have a hard wired shore power cord.