I played this for the first time with my gf on Flexgames. I had played an ordered clan of 4,5,6 green. She played a yellow 8 on the same stone. I was given the stone right after that. Nothing in rules I have seen state that you need to play a higher ordered clan of the same color to take the stone. She could have played a 7,8,9 of yellow.

What is the rule clarification of this?

If you place a higher ordered clan of any (same) color you can take the stone. I don't really get why you got that stone after she played a yellow 8 there unless the 7 or the 9 of the given color was already played somewhere else.