Interesting that you mention the Christmas special. IIRC, episode 5 had that distinct animation style switch for the dream sequences. Specifically, it had those glitter effects not seen in other episodes, probably why it sticks in our memories. Contacting old Fox Kids animators might yield some leads, anyone willing to …

I've read somewhere that the scene actually contains coded messages from the director about government intelligence. Might be why it's so hard to come by. If you find it, watch out for the men in black suits coming after you! 😜