Your partner signed for them so apparently has taken a level of responsibility for them. He chose to put them in the frame and hope that they would just be found while on delivery. That's really bad practice and easily avoided.
Personally, I'd say nothing myself as I hadn't signed for them and hadn't even been told the addresses of them.
If I sign for them they go in a separate tray in the back with a written list in the cab to check off.
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