I think the Maiden disguise is so obvious that it needs no explanation.
Amidala switches places with her maiden frequently for security reasons.
Qui-Gon’s expressions makes it obvious, but he goes with it. So should do the same 😃
So you can cut the reveal to the Gungans. They appear because the Queen asks Jar Jar to bring them. That also gives Jar Jar a reason to be in the movie 😉