It's possible but nobody indicated this as the cause.
I did ask several people at LIER when I was there, over 2 days, all of whom spoke enough English (the airport has about 5x more staff than it needs
) but nobody would say anything about it. And my preflight planning written enquiries were never replied to.
I see the current airport notams for LIER do not mention avgas, so they may have it now, but one has to be careful with this because an airport is entitled to cancel a notam the instant the information has been sent off for publication in the national AIP. And nobody is going to treat the Italian AIP as definitive
Thank you for the kind comments