Well I did a hunt for my old house, now my son lives in it, I know I have never had an EPC done, neither has my son, but there is one on line, also father-in-laws old house was next door but one, and the two houses were nearly the same, but results did not match, and it seemed knowing the two houses it was a drive past survey and bore no relation to the actual house.
I would say you need to consider if the roles were reversed. The landlord of late has had a hard time of it, told he can't evict people due to Colvid19 as if it is a one way thing and the landlord can survive without an income. I know my son has rented his house and all it does is mean it does not cost him double council tax, he makes nothing, he is living in my house, which had he not been living in it would have been sold, so we are strapped for cash, we have loads of assets, but does not help with day to day living.
I would prefer it if my son sold his old house and bought my old house so I had some cash, but have not forced the issue, I am saying this to say how although some landlords may be coining it in, some are also on the edge, so the last thing you want is for your landlord to be forced to sell, what you want is an arrangement where you both get some where near what you want.
So be frank, tell him you have a problem, and see what he says, he may be able to do some thing to help, last thing you want to do is get his back up, you want to get him as a friend, so he will bend and do things to help. I know if I had some one laying the law down with me, I would do all I could to get rid of him. Far better to be frank with the landlord and see what he says.