if moving and changing the directory in the JSON file does not work, how about moving the data, e.g. to /opt/mod.io, and create a symbolic link "ln -s /opt/mod.io ~/mod.io".
I'm pretty sure their main reason to move the folder is to clean-up their home folder. Creating a sym link unfortunately won't achieve this. Would be way better if the mod.io was located in the ~/.local/share folder honestly.