InfoPath Dev

I currently have an InfoPath Form that sends the data through a three-tier approval process before being sent to an Access database.  The general process is as follows:

If all Users approve the data in the form:
Submitter -[email]> Tier 1 User -[email]> Tier 2 User -[email]> Tier 3 User -[main submit]> Database

However, if at any time a user denies the data contained in the form, it is sent straight to the database via main submit.  In addition, the Tier 2 and Tier 3 Users have the option to send the form back to Tier 1 requesting changes; this is done via email.

 So, I am struggling to come up with a way of preventing users (T1-T3) from submitting the same form twice by opening the attachment again.  This is a problem if they re-submit a form after it has made it into the database.  I made a quick outline of the workflow to help visualize it.  Everything is working fine except for this one issue.

Uploaded with ImageShack.us

when submitting a particular form say 

tier 1 user submits the form - set a status flage in the some temporary list/table  that indicates that form x was submitted by tier 1 user.

tier 2 user submits the form - set the status flag to  submitted by tier 2 user.

you will need to create an additional data connection that will fetch the state of the form and check whether the user trying to submit has submitted the form earlier, if so abort the submit process otherwise continue

 So just to verify, you are suggesting to create a new table containing an ID and Status for each submitted form.  Each time the form is opened (or re-opened) I need to query the status to detect whether or not that user has submit the form previously.  That sounds like it could work.  Is there a way to assign that status without submitting form data into the database? 

The way I have it set up now, the data is not submitted until either a 'Deny' or a T3 'Approve'.  Originally I had been updating the data with every step in the process but that turned out to occasionally produce some "Record cannot be located for updating" errors.

nope there doesnt seem to be any other way, because user can always go to the previous copy and submit it again