Having various different anachronisms does make the story more comedic. Although sometimes I wish it was played straight in some cases. I understand why the author didn't do this however.
He knew about the bounty, but figured she was a different person because of how she acted.
But when the bounty hunter came in, Evans figured it out and decided to fake it, as he does.
because this series didn't get popular enough to get an anime/last longer (or author just doesn't want to reveal it), we'll never know. doesn't matter either way though