You can get the field key in the admin where you create the fields, you can show them under screen options.
I generally do not have an issue with live/staging/dev because my field keys are always the same in all environments. I guess this depends on how you transfer data between them.
It could be possible, using code to get the correct field reference after the post is created, but it’s not all that easy and would take a lot of resources/db queries to achieve, and it would be specific to the version of ACF you’re using (4 or 5)
