Rest assured, this has been taken into account. The scientists who spend their life working on this topic have had the same thoughts you had within minutes of learning about the problem. It's extremely basic stuff actually.
If it's extremely basic stuff and they've spent their entire life working on it, why did the two teams find different results?
Thinking of objects moving 10% of light speed, or even two times the speed of light away from you, is not intuitive to a layman, and I can't imagine the Math.
