GlideAjax script not working

[brogaming70]

I have a record producer, which is having some variables and variable set. There is a variable legal_entity (reference field) that populates the logged in user company. I want to use this company value in my script include function to fetch some data. As I am using script include function in the reference qualifier of one of my variable (budget) and this variable is in the variable set. 
I have used glideAjax client script to send the legal_entity value to the script include but it is not working.

I have already tried getBudget(current.variables.legal_entity); in the reference qualifier.

Any help on this is very much appreciated. Attaching some screenshots for reference.

Thank you