Yes, when I was writing the post I had the idea to filter based on "something" but that something in every case seems to be the script name, so yeah, my bad, sorry.
I did a bit of researching and trying during a weekend but on every try/idea it boiled down to needing a script name on which script can be identified, I even tried capturing terminal output after the script is drag'n'droped, it worked, but it didn't cover the case when the script it's just added to the startup suite, in that case the script is added and will be loaded when next drawing is opened but there's no info about the path or anything because the script isn't loaded even once, for that case it requires to hard code the name into the code and search for the name in the registry. So I guess its not possible to achieve for a script to get info about its path and name using only AutoLISP.
For now I probably go with this solution, thanks.
I'll continue searching for a solution and I'll post it here if I find one.
Thanks all for help!