Re: How to find the line that leads to St. Elizabeth of Hungary
Not sure how you would find that line since it appears there may be problems with the lineage of Randle Grovesnor. Per "The Magna Charta Sureties - 1215", fifth edition, by Frederick Lewis Weiswith additions and corrections by Walter Lee Shepard, Jr. with William R. Beall, there seems to be a problem proving the tie between your Randle and his purported great grandparents.
Citing line 98A - the line breaks due to inadequate proof of the parents of Randle Mainwaring of Carincham, IPM 3 Hen VII (1488), naming Randle aged 18 eldest s. & h.; m. Margaret, dau. of Hugh Davenport, Esq2. of Henbury.
Randle Mainwaring was the father of Margaret Mainwaring, who m. Randle Grovesnor of Bellaport, co. Salop, b. say 1450-6, d. 1 Mar. 1521/2 IPM, 8 July 1522. That Randle was the father of your Randle who married Anne Charlton.
If your "Elizabeth" line goes through Anne you may do well in looking for the Charlton lineage under Cherleton which I believe is the more common spelling for earlier members of that family.