[mothered]

I can't exactly say for sure, but it was left in the doorman building (I can't tell if doorman personally accepted it).
I tried to determine it with the proof of delivery on the shipping website but it doesn't show who signed.
I think carrier signed himself but it's an information I don't know for sure.

Understood, It can be quite difficult to pinpoint the exact events.

As per my previous post, you have enough ammunition to hit them hard. And they have a lot of answering to do.