Go to Reports > Custom Form Submits

Use the selection criteria to select the Custom Form. (you can add additional filters like Year of Entry and Calendar Year of entry to your selection as well as whether the form has been submitted or not).

Once you have selected the form and any other filters you require a list is displayed

If there is no PDF, the form has not been submitted.

Note the selection criteria for Submitted has not been used in the example.

You can use the Export option to produce a .CSV file with the completed form data.

If the Filter for Submitted NO was used you can also use switch to the Profile view and send an email requesting the form be completed Send Bulk Emails