As I said in my first post, I tried the tutorial you linked. I moved all the files, multiple times and nothing changed. And yes, I know you can remove electra with that, I've already done it a few times, but it's not worth it.
Certain jailbreak files stay in the phone and they create a mess, for example last time I used it and jailbreak with electra again, my tweaks didn't work and I had to change the tweak inject folder and create a new one cause installing tweaks from cydia was useless cause they didn't work properly.
And no, I'm not that noob. I install the cracked ipa you suggest in your post to finish the tutorial and once I did that I try to sideload the ipa with the hack and it gave me that error.
So yeah, I'm 100% sure I did everything you suggest and yet I'm not be able to get it working. I don't know what's the problem, really. Maybe is something you can't understand cause my English is not so great or maybe the problem does not have a solution you can think of.
I think we can both move on at this point ?