I am looking for some help to use Target to fire 3rd party tags (few js files) so that I can control on percentage of users the tag fires. SO basically gonna be a A/B test where few users tags fire and few it doesn't. We want to do this to validate if this vendor is contributing in increasing our conversions. Currently we are firing those tags as a page load rule through DTM.
In VEC you can use the “</>” menu item to insert any kind of code right after the body tag. So, technically you can do it. But depending on the complexity of the js tags, there may be side effects, and you need to test it thoroughly.