Hid my root, now cannot "unhide".

[AC Question]

Galaxy S5 - I rooted my device, then tried several methods to hide my root to install an app. It was not successful in hiding the fact that my phone was rooted, but was successful in "unrooting" my device. (But the app still thinks it is rooted.) :/ I then gave up, and tried to unhide it. This also failed with a su binary not found message. Now I am unable to reroot my phone. I have tried several methods. I know I could just factory reset and start over, but if anyone else has had this problem and knows of an easy fix that would be awesome. Thanks.