Unless the name of Dr. Tokugawa shows up in the ST III novelization or other expanded universe materials or is mentioned in another dubbed version of the movie, "Thorndike" or "Thorndyke" is
canon according to the German dubbed version.
I'm not saying that you have not experienced Star Trek unless you have listened to the German dubbed version (for TOS this Klingon proverb might however apply
), but every German fan of Star Trek "knows" that the Excelsior
was designed by a person with the aforementioned name.