this is the screenshot of an ideal csv as shown to me by your colleague. It conflicts with your suggestion.

https://snipboard.io/of2tbS.jpg

Also I tried both. It makes no difference.

Advice to all reading this. Avoid Quickbooks support when you have CSV issues. I found a guy in India who has identified the problem in 5 minutes for $5.

Quickbooks support was going on for about 7 hours or so. And they tell you the wrong stuff.  I spent about 10 hours on it in total.

Thumbs down to all QB support, phone, chat and here.