You will have to read the lookup within the PCR Data, in your example not only do you have to "Read PCR Data" but you should also read the "PCR Change Type" lookup (in another element) which is in the object you are already reading.
The filtration will be something like 'ID = Read PCR Data.PCR Change Type'.
Extra** The reason you got your result (and why it is still technically true) is because you are only reading the UID value of the lookup and not the Name value - there is some magic that happens to connect the UID.Name in the view. So what your code is doing is casting the UID 'type' to string 'type'.
