You'd have to do it a bit programmatically, I think. If you're using REST and you call "Get Activity Types" This is what comes back for a form fill. Note the primary attribute is form fill ID. I think it would involve calling all activity of a certain type (or types) and then parsing the jSON response for the form ID you're interested in.
Note that the form ID is the value after "FO# in the editor.
does that help?
{
"id": 2,
"name": "Fill Out Form",
"description": "User fills out and submits a form on web page",
"primaryAttribute": {
"name": "Webform ID",
"dataType": "integer"
},
"attributes": [
{
"name": "Client IP Address",
"dataType": "string"
},
{
"name": "Query Parameters",
"dataType": "string"
},
{
"name": "Referrer URL",
"dataType": "string"
},
{
"name": "User Agent",
"dataType": "string"
},
{
"name": "Webpage ID",
"dataType": "integer"
}
]
},