You got two contradictory recommendations because there is no one correct thing to do.
Rather than trying to memorize the exact behavior you "should" do in every gray area, I think you would be better served by remaining calm, thinking, and responding to your circumstances in a way that you can justify based on your knowledge of all the risks involved.
A safety stop is, by definition, a stop that is not typically required in order to avoid DCS. If, according to your dive table or computer, a stop is recommended, then it would be called a decompression stop not a safety stop. So, when you say "safety stop" it means that your dive table or computer estimates you do not actually need a stop to avoid any ill effects.
With that said, the table or computer does not know exactly how much nitrogen is in your body, because your rate of nitrogen absorption may depend on personal factors that are outside of the computer/table ability to monitor. In addition, everybody's body might be slightly different.
Therefore, the risk of getting DCS as a result of skipping a safety stop increases as you approach the limits specified by your dive table/computer. That is, as your NDL time approaches 0. If you just jumped in and got 21 ft deep after 30 seconds, there's basically zero risk of getting DCS as a result of skipping the safety stop on your way up. On the other hand, if you have 30 seconds of NDL time left, you probably don't want to skip that safety stop.