The script is onyl for mi4c. I have an idea take the userdata partition and flash it with fastboot. It will erase all data but you will get your 32gb completely
You have to extract from a working rom like you said on 7.2.4.0. download rom and then extract with winrar modem1 and modem2 files. I'm not at home so i cant see if there are 1 or 2 files or more...
I dont know if it works but you can only flash modem's file of a different rom. I did it on my old oneplus One and worked. I left intact the original rom but i changed modem files
If you dont have a backup it is very difficult or impossible to restore original values,but if you find a way to do it please share it to us, can be useful for others