nightmare, if you would like, I can send you a piece of actual harness with a sensor tab on it that you could splice in. Post a photo of the wire and I can probably even match the color scheme.
You could remove the plastic ferrule and just use the crimp. The plastic ferrule is there to grip the insulation part of the cable which, in this case, doesn't exist. Posted via the PriusChat mobile app.
Toyota soldered those connections for a reason. Crimp is pretty substandard, prone to coming apart or oxidizing. Do it right or don't do it at all.
Here's where to find the replacement. Are you sure they did? Hard for me to tell from the photos I'm finding, but they look crimped to me. There's a difference with crimp connections between properly-executed and ham-handed (and a similar difference for solder, as it happens). Properly-executed crimps are gas-tight cold welds and will not oxidize or come apart in the contact area; they're the overwhelming choice in auto, marine, and aerospace where there are wires and vibration. (Solder is still king on electronic circuit boards and such, where stuff doesn't move; open any of the Prius ECU's and you'll find plenty of solder there.) In the case of this particular harness, which is high voltage and weirdly skinny, I would not have crimped it or soldered it; I would have bought a replacement. That's not a judgment of relative merit of crimping or solder, but only of my chance of executing a field repair as reliably as they can build those in the factory.
You can buy entire used wireframe for $40 or less. Just search for the words wire frame prius. This way you'll have extras when some more go bad. You don't really need insulation on the crimp terminal.
I too am working on a Gen 1 traction battery with the same issues. I am looking for a solution to the leaking electrolyte. I think if we use an O ring on the lug that sits just proud of the copper, then when we tighten the nut, the copper bar compresses the O-Ring and seals the leak at the gap between the plastic and the metal. O ring material must resist alkaline, so EPDM, here is a link to one site but the size is probably wrong. I need to measure what is needed. AS001-70EP | AS568-001 EPDM O-ring 70 Durometer (EP/ EPR / EPT) Need 76 of them, 2 * 38. Also need to measure the size. Any thoughts on this problem. If we re-hydrate the cells it will just leak again, so re-hydrate and seal externally is what I am thinking. If someone has already done this or something similar please let me know.