The frantic parents of an alleged ISIS-loving  wannabe terrorist said they had no idea he was part of a bomb plot at Gracie Mansion and feared he may have killed himself when he fell out of touch Saturday. Teen Ibrahim Kayumi’s disappearing act prompted his mother to file a missing-person report Saturday, with her telling cops at the time that she last saw him at roughly 10:30 a.m. in their lavish suburban Pennsylvania home , prosecutors revealed Monday in court documents. The missing-person