I called the German KVR in Munich and they said I would have no problem to fly from Milan if I leave Germany before the expiration of my permit (period of two weeks between leaving DE and flying from Milan). But when I received email response (sent before call), they said I need to contact the Bundespolizei. So waiting to hear from them.
Also, Italy requires you to declare your presence if entering by land, so maybe that can help with your paper trail: https://www.poliziadistato.it/articolo/31013
The Bundespolizei answered:
"A longer-term, lawful stay on the basis of a Schengen residence permit or a visa for a longer-term stay may be immediately followed by a short stay as a visa-free third-country national or on the basis of a Schengen visa. This applies regardless of whether the longer-term stay was completed in Germany or in another Schengen state.
In any case, once the visa or residence permit has expired, re-entry via the external border is required so that the entry requirements can be checked.
In principle, a short stay is possible after a longer-term stay. However, you must leave Germany and the EU after your residence permit expires. You can then re-enter Germany via an external EU border without a waiting period. The person must then undergo an examination of the general entry requirements in accordance with Article 6 of the Schengen Borders Code (SBC)."
This was from a direct email with an officer.
I'll take a 10euro flight to Albania.