I get what Hells saying, and I have to say the 2 jutsu's look very similar, just a little bit of word play to make it look different too good to be a coincidence
But in saying that, can you please clarify 2 things if you could Hell; isn't mud an element created using water and earth? and it's shown in Narutoverse to be used by by ninja's freely which means that it's not even a KG element or CE
Secondly it's not uncommon for people use different elements to create jutsu's that essentially follows the same concept, we see examples of this in cannon and in NB i.e. all the clone's essentially follow the same concept.
So in my personal opinion what Eddy has done is to steel your concept of the jutsu, which is ethically wrong and immoral, but unethical doesn't mean illegal, so even though in principle I agree with you, in theoretical terms Eddy has done nothing against the rules, because there's no rule against using a concept of a jutsu to create a new one.