There's a lot I'd like to say, but frankly I think you just want a solution rather than hindsight.
Stop spending money at that dealership!
Get yourself an OBD2 reader, an Android device and SoulSpy.
First: Stop spending money at that dealership!
While all those services are legitimate, were the actually needed?
I bought my car at ~115,000km over a year ago and currently have 149,000km on the odometer. I've been to my dealership at least 6 times and have yet to pay a dime for anything. Every time they've done a BMS check. Once they did a BMS "update", and the last time they did a BMS check while also doing a brake recall/update.
It's good your car had those services done, but frankly I'm of the opinion that their motives aren't in your favor. Checking the BMS takes them 5 minutes (seen it first hand) and involves nothing more than plugging in a little dongle, waiting for about 10-20 seconds, results pop up on their handheld tablet, and they unplug the dongle. That's it - other than them sending it off to corporate for warranty approval.
Second: Get yourself an OBD2 reader, an Android device and SoulSpy. (if you haven't already)
In my experience with my on-going warranty saga: it was only when I told them that I had an OBD2 reader and app that they changed their tune. Up until that point, State of Health wasn't a thing, that the battery was fine and that only when an error light pops up that there is an issue..etc etc.
It's also an amazing tool and every EV owner should have one.
On your next check, don't pay or buy anything, and tell them that they need to resolve this sooner than later. Whether you contact Kia Corporate before or after is your choice, I've decided to wait until my next BMS check just because I'm more curious to what they'll come up with as an excuse vs my actual need for the battery to be replaced (as of yet..). Regardless, it seems that Kia is hesitating now with battery replacements vs before, but it seems those who escalate it with corporate get results - however yours experience may vary.
And lastly: Good Luck!
I've been dealing with this since July and I swear I'm going to have quite the story to tell by the end of it. Unbelievable, but hopefully persistence wins in the end.