Bosch staged a dramatic walkout earlier this month -- in an evening gown and high heels -- from a meeting where she was lambasted by Thai organiser Nawat Itsaragrisil.
In a livestream of the event, Nawat seemed to single out Miss Mexico during a dispute over her apparent failure to post promotional content on her social media.
After Nawat called for security to intervene, Bosch staged a walkout flanked by Miss Iraq.
Nawat later apologised.
Other drama in the run-up to the final round included two judges quitting this week, with one alleging the contest was rigged by a "secret and illegitimate vote" held without the official jury.
"This vote was conducted by individuals who are not recognised members of the official judging panel," French composer Omar Harfouch wrote in a statement posted on Instagram.
And Miss Jamaica Gabrielle Henry was hospitalised after she fell off the main stage during an evening gown showcase, president of the Miss Universe Organization Raul Rocha said in a statement.
Miss Universe Jamaica public relations director Shannon-Dale Reid told AFP late on Wednesday that Henry was "resting under medical observation" and had not suffered serious injuries.
He declined to comment on Thursday about her condition and the cause of her fall.