There are some problems with that given pedigree, not least of all the fact that Henry 3rd Baron Scrope of Masham K.G. died (beheaded) childless (in 1415)!
The lady Joan le Scrope who married Henry 2nd Baron FitzHugh was in fact a daughter of the beheaded Lord Scrope's grandfather, Henry 1st Baron Scrope of Masham (d. 1392).
Also by Margery Mowbray who married John 2nd Lord Welles I assume the author meant Eleanor Mowbray who married John 5th Baron Welles. They were not parents of Margery de Welles, rather John 5th Baron Welles was her brother!
At that point I stopped looking for more errors.
You seem to be seeking Royal Descents from the Plantagenets here, but this is the best I could find (of two lines, both illegitimate) for Eleanor FitzHugh -
1) Eleanor FitzHugh (d. 30 Sep 1457) daughter of Henry 3rd Baron FitzHugh (b. c 1358 d. 11 Jan 1425) and
2) Elizabeth Grey alias Marmion (d. Dec 1427) daughter of Lora de St.Quintin (b. c 1341) and
3) Robert de Grey alias Marmion (d. by 30 Nov 1367) son of John 1st Baron Grey of Rotherfield (b. 9 Oct 1300 d. 1 Sep 1359) and
4) Avice Marmion (d. after 20 Mar 1379) daughter of Maud Furnival (living in 1348) and
5) John 2nd Baron Marmion of Wetrington (b. c 1292 d. 30 Apr 1335) son of Isabel (de Peck?) and
6) John 1st Baron Marmion of Wetrington (d. by 7 May 1322) son of William Marmion (d. 27 Jul 1275) and
7) Lorette de Douvres daughter of Rose de Douvres (d. 1264/5) and
8) Richard fitz John, Baron of Chilham (d. by 24 Jun 1246)illegitimate son of
9) John King of England by Suzanne, perhaps sister of William de Warenne Earl of Surrey.
The other line I found was through King Johns illegitimate half brother, William Longespee Earl of Salisbury.
There could possibly be more lines to be found, for example as far as I know the parentage of the wife of Henry 1st Baron Scrope has not yet been determined.
Another point of relevance is that the marriage of Sir Thomas Tunstall and Eleanor FitzHugh must have taken place between 2 Aug 1418 (the date her 1st husband Philip 6th Baron Darcy of Knaith died) and 18 Feb 1427. Statements that their children were born before 1419 should therefore be treated with caution.