Validation succeeds without new taxonomy terms

Steps to reproduce the bug:

• Use the https://www.drupal.org/project/msnf module
• Put a required Tag field in a step which is not the last
• Insert only new Tags in the field

I would expect either:

• Form validates to true
• New Tags created on the fly
• Tags associated to the new node

or

• Form validates to FALSE
• New Tags created on the fly
• Tags associated to the new node

Currently this happens instead:

• Form validates to true
• No Tags are created
• New node is created with an empty required Tag Field