All of them look similar to very popular memes I've seen on the internet. No doubt that the others are traced. However, the only proof I have is what they call the 'angry chibi meme' or something to the sort.
I do not know how to make the mini animation where it compares between the two, so I will just leave the file here of what I am referring to since there are multiple.
As for your situation, I am sorry you have to go through with that. I hope that they come clean with you and are honest about it.