Audio issues with my FMP

When it came to filming my FMP on Monday the 21st May I was planing on using a lapel mic with the H4N Zoom mic. I had a lot of troubles trying to set it up as the lapel receiver would not click into the H4N Zoom mic, due to this issue I resorted to using the H4N Zoom mic on its own as I thought that it would still pick up the talking clearly but it didn't. Instead it picked up the noise around it more than the subject talking. This error caused the audio from the H4N Zoom mic unusable. Luckily, I had set my Rode VideoMic Pro up on top of my camera. It managed to pick the subject up talking slightly better than the zoom mic. I have had to use the audio from the shotgun mic on my camera as it was slightly more clear. This is the only thing that I strongly dislike about the video as it is very unpleasing to the ear. I have tried many different things to try and improve the audio such as putting both of the audio tracks over each other but it only made it worse, I also tried to use a few audio filters on the track such as a de-noise filter and it made no difference because it was reading the subject talking as noise and was just removing the subject talking. I have not found a solution to my issue so I had to use the audio that I have. I am not able to re-shoot the video as the lessons only happen on a Monday and next Monday is a bank holiday and the Monday after is the deadline for this project and I can not film in the week as I do not have contact with everyone and people usually only go on Monday for the lesson only so I do not have any other option but to use the bad audio that I have.