Here is what I found.......
Alice Bredwardine (the Bredwardine's were the ancestors of the Vaughans) was the mother of Sir John Scudamore who had secretly married the daughter of Owen Glyndwr.
Interestingly, the Glyndwr legend is not unlike that of Cornwall's King Arthur, where it is said that he will one day appear to save his native Cornwall, Glynwr too is set to re appear to save his beloved Wales.
A statute had been passed which forbade any Englishman with an alliance with Glendwr from holding any office, so Scudamore was stripped of his titles. The Scudamore’s son, was Henry, it was this Henry who was captured after Battle of Mortimer’s Cross, along with John Throckmorton and Owen Tudor, although he and Throckmorton may have escaped execution at Hereford, Owen Tudor, was not so lucky, his executioner was Roger Vaughan, the great great grandson of the Bredwardines (not Alice's line I must point out.)
Here is a link to my blog if you wish to read where Henry Scudamore, Owen Tudor and Roger Vaughan fit in.
http://meanderingthroughtime.weebly.com/blogs-on-the-wars-of-the-roses-1376-to-1478/vengeance-is-mine