I think the shadow ban is just for the hashtags not for the picture!! I think if you tried it manually it will work, but the shadow ban won't show this picture in the hashtags you use + will limit the people who follow you to see that post!!
but the picture won't even be posted on your wall that means something else is going on on your account!! try to report a problem from the app once every day until you get fixed, i am saying this Cuz i am shadowbanned right now, i know how annoying this is
i know IG problems can be great pain, Sorry.