His name was Sorn and he abducted the princess of Dol Amroth that was at Scarburg for a little while. "Abduction in Edoras" was the rpg and can be found in Elvenhome. From it Scyld was introduced, not to mention Scarburg itself, but without that name.
So there never was an eorl at Scarburg until Eodwine. Just setting the record straight.
Might be a useful tour of about 4 pages if you want the background on Scarburg,
G55. 
http://forum.barrowdowns.com/showthread.php?t=12824