We have two backup databases that we can login to see if the content is still accessible. One of the databases updates frequently the other is less frequent.
The availability of recovering these items is depending on when the items were added and when they were deleted. For example lets say yesterday you had something on your site. Today you went in and deleted it but then realized you needed that back. There is a bigger chance of having that item to recover. If you added it today and deleted it today it will not be available to be recovered.
It is imperative that you let us know as soon as you delete the Custom Form, and the Title of the form so we can try to recover the data from the backup database, or at least obtain an Excel File with the Data intact from the backup database.