This could be a "challenge" and there may be a Catch-22.
Bikes manufactured for original sale in the US do NOT meet EU standards, or are different in certain respects from EU standards. Whether those differences matter to your Italian authorities is another question.
BMW North America & US BMW dealers do not have the specific data/ information on exactly what those differences are. Therefore, BMW NA cannot create/produce a statement that would meet the Italian govt requirements for a " Scheda Tecnica Rispondenza Normative UE."
Likewise, BMW Italia probably does not know the differences between EU standards & USA standards.
It's possible/ probable that the only BMW staff who actually know the difference(s) between US standards & EU standards are located in the BMW/ Munich corporate office, or at the BMW bike factory in Berlin.
I would suggest that you [try to] contact the BMW Motorrad Italia corp office
BMW Motorrad Italia,
Contatti
BMW MOTORRAD
Indirizzo postale:
BMW Italia SpA
Ufficio Relazioni Clienti
Via dell'Unione Europea 1
20097 San Donato Milanese (MI)
Telefono : 02/51610111
Fax : 02/516100187
e-mail :
bmw@bmw.it
and ask them to help you to obtain the information from BMW Motorrad/ Munich, i.e., give you the name/ contact of the correct Motorrad office in Munich or Berlin.
Some of this challenge is what level of technical detail is actually required for the official Italian document. The less information required for the Italian document, the easier it may be to get that info from Munich/Berlin.
good luck!