Exactly I used the external url for the param. I guess using internal linking with params is not a thing as of now then. I will make sure to use your workaround so the urls are sort of dynamic.
Last question I promise 
: Would there be a way to transfer the information from the button to the form if instead of a new page it’s implemented as a popup? In that case I wouldn’t be able to link to the form as it is still on the same page technically speaking, right?