Ribbon cable PCB connector repair
Had a similar situation recently. The steps I took were to put two layers of Kapton tap on the underside of the break to prevent further damage as I worked on it. I then exposed the copper each side of the break for about 3mm with the tip of a craft knife. I tinned this exposed copper (Kapron tape is heat resistant).
used very fine tip iron 0.8mm and very fine wire - I joined the copper with strands of fine wire - strands inside light test leads work best. When soldered I then used heat glue to keep it rigid. Contemplated using Araldite but reckoned that if a connection subsequently lifted I would have difficulty - heat glue can be melted away and the connection can be reworked. Once I put the piece of equipment back in situ I was able to further re-enforce it accommodating its natural curve.