I'm not sure if you now have what you need or are looking for something else.

Original problem stated:
setup "find" command allowing to find all files or directories according to a specific filter whatever case sensitive


The suggested fix will do that.

To add it to your script would be simple.

If you need more than that, respond with more information.
If you are looking to filter more out of the output from the find comand (piped to grep) you may need to be more specific in what you are greping for (add another grep with -v option to get rid of what you don't want?)