+delete dat file you have in game folder or save it outside main game folder
+use steam integrity check
+download random data mod not too complicated from browse mods
+you will find it in /user(the folder where you find the folders documents/video/music etc)/game/aoe2de/randomnumbers/subscribed
or something like that
+delete its dat (inside subfolder of the mod)
+go to official folder and copy its dat and paste there, on the downloaded mod or use the previously saved modifed dat and paste
+move entire mod folder to local mods (copy it, its better)
+go to aoe and choose import mods on the mods submenu
+open advanced genie on the local mods dat file you just created/pasted and not the official game folder dat
+everything should work now
+if you go to your mod list, the previously downloaded mod should still be there
+if you are unable to delete it/unsubscribe from it
+there should be a json file inside the aoe2de/randomnumber/subscribed folder where it lists your mods downloaded
+open with some text editor
+delete the voice that contained the downloaded mod name
You can use your modified dat only as a data mod.