Did I violate TWOV?

There is no doubt that you have violated TWOV because you have returned to the place where you came from. As you can see, this way not a transit, but a visit to China or in other words, this was a return trip. Transit is only then when you are going from country A, through country B (China in your case) and after country B end your flight plan in country C. You did not do that, but you have done a scheme A - B - A. This is a clear violation of TWOV. Also, if you are a citizen of Thailand or/and Russia, you had a right to stay for 30 days (as Thailand citizen) or 144 hours (6 days) as Russian citizen. In other words, you were able to wait those 4 days completely legally and proceed to your final destination. However, you have accepted the proposal of an airline and in that moment you have clearly violated TWOV rules. In the case if you were Thailand citizen that would not be a violation because Thailand citizens have right to bypass TWOV rules since they have right to stay in China for up to 30 days visa free.

Now, what could arise from the entire situation is definitely unclear, but if your passport was not stamped with some kind of denied entry remark, I would say that you can proceed with your travel plans, but I strongly suggest you to find a flight plan that will have a shorter layover in China, so that you can remain within airside and not to exit the airport. The reason for that is simple. When remaining airside, you are not a subject of immigration and/or customs control, but you will just cross a security check between two flights.

The problem is that the Airline put me on that trip back to BKK not knowing about the repercussions, and the Airline made me apply for a 24-hour visa-free stamp knowing I wouldn't be on time for my flight! Why did this happen? I cannot answer, clearly, there was no system in place to deal with such contingencies.
AirChina contacted Beijing Immigration about my case and the immigration confirmed that I and my children are now banned from travel. Was I to travel on July 16th, I would be turned around at immigration and AirChina would have to send me back again at the company's expense. I could not subject my children to this stress again so I did not travel and applied for flight change instead.

Anastasiia, I perfectly understand you and I am more than convinced that you were doing everything by having full trust in what the airline is doing/suggesting. However, they have done wrong moves and they have definitely put you into the situation where you have breached the rules. I hope you understand that the Chinese authorities simply do not want to investigate whose fault was in the case of your breaching of visa free transit rules because it was you who bears the sole responsibility in keeping the rules of the country whose territory you are using to transit. I am sorry because you are banned from entry into China, but I also hope that you will be able to find alternatives as you have already done for your following journey. In any case, I wish you all the best and also that a ban imposed on you to expire as soon as possible.