Yes, this is present in the release version - and not restricted to oil or tranches of 2. Basically, it works currently "fine" in my save with selling single pieces of coal to an allied civ (Korea) for 10 Gold and 6 GpT. Steps to reproduce:
1. Offer AI 1 coal and ask what they would give for it
2. AI answer: 1 Gold
3. Replace that AI offer with the default 10 GpT, they find it unacceptable, so ask them to put up a fair deal
4. They come up with said 10 Gold and 6 GpT