I have never really noticed those similarities *lol* to me it doesn't matter who came up with the idea first because I always thought those moves displayed in the posted gifs were typical 80s moves
Remember Michael said that he told Janet to use a military style for Rhythm Nation way before he used that kind of choreography himself. We don't know what they did at home when they met, what moves they showed each other or by what or whom their choreographers were influenced. It doesn't matter. If Janet came up with something new, it doesn't mean that Michael was less amazing. He was a genius!
Anyway, I think it's fair to say that Janet is very talented and showed us some great moves in her career.