Williams certainly likes to screw around with traditional hymn-like tonality, doesn't he? My advice is to treat a lot of the weird harmonies as they are - created by a whole lot of dissonant passing tones that really don't add up to much of anything when analyzed traditionally.
Williams treats a lot of chord functions loosely, a la Prokofiev. The penultimate chord in this cue looks nothing like a dominant chord, but it certainly sounds and functions that way.
That's all I can say about this - I too stumbled across this a couple years back, and said 'wtf?'
But I actually LOVE this cue, just for it's kooky use of harmony.