Hiya! I’m sorry to hear you’re having issues with reinstalling WeMod.
I know you’ve mentioned following other tips on the forums, but I haven’t seen a mention of deleting the old WeMod files, so that’s always a good try.
Try following the steps laid out by Ravenfyre in this post. 
I can’t Install WeMod / "There was a error installing the application" - #2 by Ravenfyre