Mk1 rust favorite spot or ... more serious scar?

On my prior-to-shipment Mk1 pictures I see a grey painted welded patch in the trunk floor, somewhat left from the image center. Do You think it’s just an old rust repair or an indication of something more serious happening in the past ?
I’ve heard of braking Panhard’s rods or so … might it be a perforation scar ?

Very odd.
I have a MK2. No rust in that spot. Very clean on both sides. I would guess it is not a perforation scar from the panhard rod or you would have lots of damage to the whole panel around the area as it punched through.