if mail is mary123@gmail.com
and misspelled is your database is mary1230@gmail.com this is another email
if exists but never opt-in your list may be in the spam (in most cases)
if now this misspelled mary1230@gmail.com does not exist as an email then will be bounced.
that's the way I recommend some basic verification is done before sending by mailwizz
I think a good start is for Mailwizz to make a basic verification in a period of time example 1 time per month like:
Domain & MX Validation, (domain exists)
SMTP Verification, (username exists)