> I mentioned that Chad's flag is identical to the Romanian flag.

I find this unconvincing evidence because: you already knew this (somehow) and found it an interesting piece of trivia to bring up at that time. It's unsurprising, then, that a YouTube channel also finds it interesting.

It's very likely that you were influenced to remember this piece of trivia because of something you observed, like (for example) subconsciously spotting an advert.

These are common advertisements. You only noticed them the next day because you talked about them the previous day.