Adam is pretty good in the 1968 Rome Siegfried, too, conducted by Sawallisch.I second my praise for Donald McIntyre, but I would really like to appreciate the opposite direction that Theo Adam takes compared to my favourite, Hans Hotter. Adam represented in the late 60s and early 70s the type of young Wotan that would star in the last generation of great Wagner singers. He is definetely in average level in the Janowski Ring. But the recordings where I point out the passion and intensity he brought to Wotan are in the Böhm Ring (Das Rheingold from 1965 in mono and Die Walküre and Siegfried in 1967-67 in stereo).
A couple of other potential passages might be the passage that begins with "So nimm meinen Segen, Nibelungensohn" in Act 2, or "Wo ist Brünnhild'" from Act 3. Or you could use the first third of the Abschied.I wanted to include a Wotan piece for the contest but everything he sings is so long winded to try to fit in a reasonable time slot.