She was credited, see the original W&C paper: https://www.nature.com/articles/171737a0 at the end is an acknowledgement. She also has a related article in the same issue of Nature.
I wouldn't be so sure that Franklin would have figured out that DNA was an antiparallel double helix. She knew it was a helix from the fibre diffraction pattern, but I don't think just anybody would have had the insight W&C did about it being a double helix and antiparallel, which immediately suggests a possible copying mechanism for the genetic material. However, we can't know for sure.
Edit, in re-reading https://www.nature.com/articles/d41586-023-01313-5 I see that she did suspect the DNA structure contained multiple chains. So my statement about about the double helix aspect was incomplete/incorrect.
I wouldn't be so sure that Franklin would have figured out that DNA was an antiparallel double helix. She knew it was a helix from the fibre diffraction pattern, but I don't think just anybody would have had the insight W&C did about it being a double helix and antiparallel, which immediately suggests a possible copying mechanism for the genetic material. However, we can't know for sure.
Edit, in re-reading https://www.nature.com/articles/d41586-023-01313-5 I see that she did suspect the DNA structure contained multiple chains. So my statement about about the double helix aspect was incomplete/incorrect.