Two options that the administrator can use to solve this scenario are:

Create a custom object. A custom object is an object that you define to store information that is specific to your organization or industry. In this case, you can create a custom object for the form that has more than 30 fields and relates to the account or opportunity object. This way, you can store multiple submissions of the form for each account or opportunity and track their changes over time.

Turn on Field Tracking. Field tracking is a feature that allows you to monitor changes to certain fields on an object and display them in a history related list. In this case, you can turn on field tracking for the fields on the form custom object and see what values were changed from one submission to another.