Orsato is FO which probably means that he has a CL appointment coming.
Mariani with a match on Monday which doesn't forbid an EL appointment.
I’m guessing Orsato is building up his fitness after his elongated lay off. I would also think he will get an important observer to see what his current levels are for CL.
I don't believe that he will get a special observer since he is a lock for Euro, he did the CL final and generally he is considered a safe pair of hands.