I did find a way, but it is too long. I just made an extension of the above macro. So; the macro navigates to the session folder in Finder, copies the file path, goes back to ProTools, chooses Export Selected Files, presses the button Choose... and sets the folder to the earlier copied path+/Bounced Files. So yes, it works, but i don't like it. It is way too long.
The problem is what you already asked in the start topic; how to get the path of the current session in a variable.
Here is a demonstration. It works most of the times but i don't like the way how i did it.