What a tangle.
I agree that the marriage records don't seem to relate to anything on the profile. The marriage mentioned in the bio in 1644 and the one for Francis in the references are children of the Earl of Buccleugh. His profile; Walter Earl Buccleugh
It looks like there have been a lot of changes in the profile over time.
Walter started out as a son of Walter and Mary .Then dates were added then later changed by someone else. John and Isabel were added as parents.
James started out as a William son of Walter and Mary . As William he was merged with William of Harden in March 2015. In April 2015 his name was inexpliquably changed from William to James. His death date was altered (the change to James was made by the same person who added John and Isabel as parents of Walter.)
Mary, the wife of Walter was created as unknown but was also said by the profile creator to be the daughter of Walter and Mary Scot.
Several have decided that Walter was supposed to be https://en.m.wikipedia.org/wiki/Walter_Scott_of_Harden (the ancestry tree also goes to 'his' profile). https://archive.org/details/scotspeeragefoun07pauluoft/page/73/mode/1up/search/Scott
It does seem to 'fit'. (Well at least with names, I can't see any dates at the original creation)
BUT We may have at least two other versions of this Walter: Scott-16036 and Scott-25546 but each has a different father(onr Walter, one William ).The wikipedia article says the father was William. The Scots peerage is hard to follow but seems to say father Walter (not positive I think you need expertise to read these pedigrees properly and I don't have that) Walter appears to have married firstly Mary or Marion d of John Scot of Dryborough ( Scots Peerage p 74)
Conclusion; We need an expert .Seriously there are a couple of members who have a lot of expertise in the Scottish peerage. At the moment it appears Walter and his son have been changed from their original personas . He may have originally been intended to be Walter Scott of Harden.(Auld Wat).It is also apparent from the baptism record that there was a Walter Scott son of John and Isabel .They may be totally unrelated to the 'original Walter'.
