Yep, assuming your calculations are correct, that means the decomposer forfeited 432 sats worth of dust that couldn't be split into equal sized outputs.
This is the uncertainty I'm talking about. The user does not know beforehand how much money will be forfeited because the decomposer treats the remainder as dust. Is there a page that explains how this works behind the scenes, ensuring users aren't surprised by paying significantly more than expected?
It's under 'Coinjoin' tab within 'Wallet settings'.
I had found that, but I assume that allows me to send only to Wasabi wallets, correct? I cannot send the joined coins to Sparrow or to a bunch of addresses I select?