Hello all. Just to clarify a few points: Flight origin was Thessaloniki, Greece. The luggage was most certainly 'complete' at that departure airport. I am fairly certain, nothing nefarious occurred at the departure point given my experiences there on previous trips, as well as the timing. Whether the theft occurred at Frankfurt airport, or via a courier in Italy, the speculation is it may have been the Italian side (either the Italian airport or courier). This is pure speculation, but based on anecdotal accounts from other frequent travelers, who have had items come up missing, there seems to be a trend, within Italy.
The European Union, as well as Lufthansa, does have pretty clear processes in how to resolve these situations. The EU allows for compensation of reasonable replacement items, for the days that the luggage is delayed. In our case, our luggage was delayed 3 days, so, within reason, we could purchase personal items and clothing for an equivalent period of time. Now, once the luggage showed up, and items were discovered missing, then an additional claim for missing items could be made. I believe there is a 'soft' number (set by either the EU or Lufthansa(?) of around 1500 Euros, that does not require any extraordinary level of justification, for lost/stolen items. Beyond that, additional documentation is required. I filled out all the appropriate claim forms, in a timely manner, now, we'll wait and see how well the reimbursement process works.....it's been a few weeks...........
Of course, this does not compensate for time spent deferring your travel plans, and hours lost having to (emergency) shop for replacement clothes.
I did read the article on the woman who tracked her missing bag via Airtag. I am not an Apple user, but it did make me think twice about some sort of tracking device in the future. Not necessarily for anticipating theft, but just for the reassurance that your luggage is on its way. I travel internationally, quite frequently, and I have had luggage delays in the past. This is the first time that items were found missing, once I recovered the luggage.