Hi Nikki, when I am proposing merges, then I always put in a lot of detail about specifically why they are duplicates and if there are differences, then which is correct or why I still think they are duplicates, or that further research is needed.
If someone has rejected a merge before than I might ask them not to reject the merge immediately and remind them that there are 30 days to work out any differences.
I also notice that neither of the Barbara Wellons profiles have adequate sourcing and sometimes adding sources can help to definitely identify they are the same.