Stupid mistake

The link itself cant heal. The OEM fusible link had a service disconnect. If you did have a brief open circuit condition, in that or the bulkhead terminals would be my guess. Something you cleaned or wiggled while cleaning was the fault.
Speedo cable and sheathe makes 90 degree turn under the drivers seat area. That's where the cable tip normally hangs, refuses to push through that turn. Jack the car up, go under and disconnect from trans or... Reach under and remove sheathe from under a sheet metal strap and wiggle it around a bit has worked for me.