That's correct. That's what I was saying. You want the original parts, otherwise when you replace the cell and cut the brand new cable to work with your retrofit, you'll void your warranty.
Call back and try again. And again if necessary. Their tech support people have discretion. Call back to get a different one that has a different notion about acceptable reasons for repair.
Or just call back and give them less info. Just say it's new and doesn't work. "Please send someone out to fix it." They might give you some troubleshooting steps, perform those, or pretend to, or tell them you already did. You get the gist.
The guy that will come to your house won't be a Pentair employee, just some pool guy who has earned Pentair authorized repairman status. He won't care about giving you a new cell and connector, it's not his money.
IMO, that wouldn't be anything unethical. Pentair uses inferior connectors. Many of us have been stung by them. They corrode and cause all sorts of problems, that Pentair foists onto the consumer. It's not unfair that they have to eat if once in a while for their penny-pinching, cost-cutting decisions.
Those connectors are part of a pool equipment system, intended to work outside in the elements. When they fail at their intended use, during the warranty period, that's on Pentair, not you.