Thank you for your reply! I feel hopeless! I installed 18.104.22.168 as you said and the same problem exists(shown in the photo (its a weird error)) when trying to redownload the app after i enabled SSL proxying! The strange think is that i ve done the same proccedure downgrading the app into 2.8.1!!! And now something magic happened!Here's a link, with detailed instructions on how to revert to old iOS app versions. It's definitely not trivial, but it does work. Be aware they say iTunes 12.5 introduced some changes related to certificates, so this method doesn't work anymore. You can find a 12.4.x version of iTunes on FileHippo.
I am sure! Anyways thanks for the try! Appreciate!!I really can't help you more. If you have a Windows PC, try that route. Is the problem just with 2.9.1 or you cannot get any version with this method? If I have time, I'll give it a shot tomorrow just to see if it works. Sorry for the silly question, but are you sure you don't have 2.9.1 in your iTunes folder (on Windows it would be C:\Users\<your_username>\Music\iTunes\iTunes Media\Mobile Applications)?