So let me make sure that I understand correctly:

The flex connector just rests against the circuit board (see my attached photo) and is held there by the pink piece of glue/adhesive/bonding agent?

It seems to me that they should have used a ZIF (zero insertion force) connector on the circuit board rather than relying on the glue/deal. What does the other side of the board look like? Would it be possible to add any sort of connector to the board?

It looks and sounds like soldering flex computer cable is the best option so far. Based on your picture I'd say with the correct soldering iron its very doable.

Good luck!

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