[مغلق] fallback to default language not working for variable products

My previous ticket was closed, even though my support expert said "One of my colleagues will be taking over your ticket." I wanna ask something in reference to that ticket. https://wpml.org/forums/topic/fallback-to-default-language-not-working-for-variable-products/

In the specific case i shared with you, what was my mistake, and how should i go about this to fix it, to work in fallback language. I need a more detailed, step by step explanation please.