Filter for "Filled out Form" with a specific form value set

Hi everyone, 
I like to filter for "Filled out Form" filter criteria while a specific value should have been given during the form fill. Do you see any possibility to do so? 

I know that there are some Constrains you can add to a "Filled out Form" activity. Constrains like ""querystring" or "browser". But there is no constrain for a specific field value. 
The activity in the users activity log contains all the values given during this specific form fill. 

I know that I can filter for "Filled out Form" activities and add a field value filter. But from what I understand this would not ensure that this value was given in the form. Maybe it changed later on. 

I know that I can filter for "data value changed" and add the constrains reason and/or source. While source contains just "web form fillout" and reason contains the whole page name. Nor the one or the other specifies the form itself. And it specifies the data value change. It would not react in case the value was the same before. 

Do you have any idea to solve this?

Thanks and kind regards
Wolfram