cant set to isValid = True

 I so close to fixing this problem i had, But again i feel the validation in a datagrid is the downfall.
customer validator works fine. untill i want it to set args.IsValid = True;
Again i think its because when validator is in a datagrid which repeats the textboxes giving them valids like
wizardpage1SelectProductOptionsComponent_dgAdditionalCosts_ctl02_txtUnitPrice where it goes ctl01 to ctl07 args is a value not a object. so it doesnt have a IsValid propertry.
Is this simply a nonfixable bug or what? javascript below
 
 
function QuantityTest(source, args)
{
//Gets unitprice object and then gets value and id out of it
var UnitPriceObject = document.getElementById(source.controltovalidate);
var UnitPriceValue = UnitPriceObject.value;
var UnitPriceId = UnitPriceObject.id;
//Edited source values to get other textbox ids then gets value and id
v ...