Hi Henrik,
Yes, you can set up this test case in Target !
There is "Add Custom Code" option in VEC modifications tab where you can add your custom logic (code) to Pre-select and hide/disable different elements (i.e. your input fields and buttons) with use of javascript, jquery or any code which is compatible with your webpage.
If you want to pre-select and hide/disable particular element (i.e. your input fields and buttons) for specific customers only, you can follow same steps as above; and you can create specific audience which you can use for targeting.
Let me know if this helps you.
have a good day !
Thanks,
Gauresh Kodg