Jenkins Active Choices Cascading Choice for 3 Parameters Not Working
The Version should be defined as an Active Choices Reactive Parameter (Single Select).
As I understand from your question, Version is dependant on the value of Environment and Branch.
You will need to write some groovy script (or use a predefined Scriptler script) that takes the values of Environment and Branch and returns the appropriate (filtered?) list of available Versions for the user to select.