Could I also say 우리들은 다 먹었어요?
the 들 is weird you can't use it like that.
like you can but it's unnatural
"우리가 다 먹었어요" would be more natural.
I accidentally said "우리들은 모두 먹었어요 "
no you were right... just a different way to say it no worries ^^