I’m having the same trouble as a UK based adult, can’t and don’t drive. Not interested in Credit Cards, only use debit. Only have BC and Passport as forms of ID. BC isn’t acceptable, but passport is only acceptable if US card passport, or an EU (card form) or the IE (Irish) card form passport.
Have sent feedback stating that the UK passport is only available as a booklet. My proposed improved flow, for scanning is to scan the cover of UK passport to identify as passport, then the internal page with the actual ID.
For those of you who are also having the same trouble, may I suggest getting Apple Support on the phone and sending feedback similar to mine. If enough of us with this issue, get support on the phone and sending similar feedback, then their developers will get the message.