Questions About Car Rental Insurance and Policies with Germanwho (Alamo)

Hello, according to the tips in the forum (thank you very much), I booked an FFAR class car for our trip through Germanwho. I have the young driver package as I am 21 when renting. My question is, does Germanwho (i.e. Alamo) insurance cover everything? We have added the Breakdown Assistance Plus. (Does this make sense?)

Additional drivers are included, but my question is, is anyone allowed to drive at all because my friends are under 21 and my girlfriend is only 20? I don’t know if the life partner paragraph applies. We’re engaged but not married, so I’m not sure if she gets to drive.

My last question (even if you probably can’t answer it anyway) how high is the probability of an upgrade for the car or how often did you happen to have a higher vehicle class in your row and if a higher class in the row you can take it at all, at the end it will be checked again whether you have the right car, I thought.

Thank you very much if you read the whole text, sorry for the long text but it’s my first trip to the USA and since I’m going there for my birthday I want everything to be perfect.

Best regards