1- Yes it’s permissible to wear them. As for the Qur’an, it always offers blessings and protection. As for Nadi Ali, while we don’t have a hadith that states to wear it, it doesn’t harm to wear it if it reminds us of the values and legacy of Imam Ali (a).
2- Allah wants to give this person a chance at this trial. Would it be fair to deny him the chance? If the teacher refuses to let this student enrolled (because he knows he will fail) is this fair? The teacher has to give the student a chance. Also, if Allah would only give those whom he’d know would pass their trial a chance, then it defeats the purpose of being tried. Allah has already created angels who are 100% good. If Allah only created people who would be good, then how would they be tried? It would negate the purpose behind the entire system. That’s like asking a question on a multiple choice exam and all 4 answers (a, b, c, d) are correct. Anyone you choose is a correct answer. Well this won’t be considered a test anymore.