Well, it's not exactly verifiable, but here is a quote from Tiamat's Plot Guide (it's not up to WP's standards, but I trust this guy personally):Okay, I finally found the official confirmation that his last name is in fact, Schugerg (well, the katakana is Schugurugu but it probably properly translates to Schugerg).  It was in a Capcom released SFZ2 Arcade
Flyer.  Whew!Hope that at least helps your doubts.