In the film as it currently stands, there's a definite unnatural-sounding pause in Donovan's line, right where the word "Jewish" would've been: "...the finest [blank] families in all of Germany." So the scene almost certainly was shot with Julian Glover saying it as originally scripted.

Personally, I'm much more curious about the claim on IMDB that in the theatrical cut of LC, a close-up of the Zeppelin revealed it was actually the Hindenburg.

If that's true, it was evidently removed due to the obvious anachronism involved -- the film is set in 1938, but the real Hindenburg had been destroyed the previous year.

As with the "finest Jewish families" line, I'm inclined to believe this, largely because in the current cut, when Indy and Henry board the Zeppelin, there's a strikingly ominous music cue that has very little relation to what's happening on-screen.