Europe
There are several strands in Biz Av in regard to your questions.
However in general you would need a work permit....a wedding is a good option, and perhaps more cost efficient....
Your FAA ATP and type would entitle you to "casual" work in Europe on an aircraft passing thru, but not a based aircraft...reference employment laws. There are Americans working in Europe, but not many.
A JAA ATP, is a very expensive and in my opinion a total farce.....
Your italian is a bonus but will not swing anything...
Until the USA permits EU pilots freedom to work there, the EU will not permit you to work here, until the playing field levels out.
Windy.