Re: "the soldering had been done with a hot spoon."
Back in the day, when our product was sold in Boots, I received a support call about the length of the connector*, could he de-solder it & pull it forward a fraction for extra clearance\pull it back for a tighter fit as he had a soldering iron....
I vaguely recall advising him it would void his warranty but stupidly trusted in his abilities it was the 80's & all sorts of tinkering went on.
Some months later... a shipment of repair under warranty devices came in from Boots, I opened up this one box & that phone call came flooding back to me, the 8PTDT switch was in pieces, heat gouges & the traces destroyed, because this guy's soldering iron was a plumbers soldering iron.
I sent it back saying this wasn't warrantable repair with a lengthy letter of my findings, a few weeks later the branch rang me up asking why it wasn't repaired, as the prototype Kieran* complaining loudly about his interface, why it wasn't repaired or replaced. It transpired that my letter had got misplaced so I took great pleasure in reading it to her (Off my Amstrad PCW8256 screen), she listened with equal pleasure & said she was greatly looking forward to informing the customer of this on his return, I think I faxed her the letter (she didn't have a email address).
*From memory this was our comms interface for the Spectrum128.
**Male version of the Karen.