Hide Table Sections Based on User Inputs

I have linked my form below. I am trying to script the "Hide Closed" button. I want to hide all of the instances of the "ActionItemGrp" table sections when the user has entered a date in the "ClosedDate" field. I tried the following script but can not get it to work.

Form1.ButtonsPage.HideClosed::click - (JavaScript, client)for (var a=0;a<Table1.ActionItemGrp.instanceManager.count;a++){for (var b=0;b<Table1.ActionItemGrp.all.item(a).Table1.ActionItemGrp.Row5.instanceManager.count;b++) {  if (Table1.ActionItemGrp.all.item(a).Table1.ActionItemGrp.Row5.all.item(b).ClosedDate.rawValue!==null)   Table1.ActionItemGrp.all.item(a).presence = "hidden";}

Link to my file on WeTransfer:  http://we.tl/bmZjwdb52u

Help is apprecaited...