The DNA Connection on Rachel's profile does not mean that it is confirmed with DNA.
When someone here builds their tree, they could have mistakes possibly.
When a person takes a DNA Test and enters the information on their own profile, Wiki Tree updates and makes a trail showing how/where the DNA from the original test taker could have come from.
The only way to confirm DNA without DNA from Rachel, would be to Triangulate.
Triangulation is not easy nor is it 100%. The amount of DNA we inherit is a bit random (you could get more from your mom than your dad, for example) and you would need to find at least 2 other people that have also taken a DNA Test. Those other 2 people would also have to have come from separate lines (For example if Rachel had 3 children and person 1 is related to Rachel's first child, person 2 is related to Rachel's second child and so on).
Even then you would need to compare all three testers and find a match on the same chromosome and in the same place, all overlapping each other.
If you meet all those conditions it does not mean that Rachel is 100% DNA confirmed, it only shows that the three test takers match and triangulate with their DNA and then as long as they have the information leading up to Rachel, they can show that it is most likely that they are all related through Rachel.
