I have a problem understanding your post.
Your problem description uses terms that only you can understand:
What is a Tab-level in a map at the Tab-level?
What do you mean I have a call to next level DataFormDlg?
How DataFormDlg is related to a Tab-level?
Could you please rewrite a post and describe what are you doing assuming that we do not have a crystal ball nor can we read your mind?