Seem like I read some where there is a trick you have to do to get the progressive industries surge protection to work with them
Ground the generator to the coach?
Neutral - Ground plug. Buy one online or make one up for about a $1.50, jumper wire between the negative and neutral terminals tricks the Surge guard. Plugs into one of the outlets on the generator.
Southwire 44400 Generator Neutral-Ground Plug (https://inverterservicecenter.com/southwire-44400¤cy=USD&language=en?gclid=Cj0KCQiA7YyCBhD_ARIsALkj54qtdPaZ95Ll7O7hiHvVVNrb69epSJhn-SvDadCrwI8jtg0XauwquVYaAjVaEALw_wcB#intro)