I am not a scientist, but I see some problems with that.
Once you determine which questions will give you the information you need, whether you put them in the short form or the long form should not make any difference in theory. If you put them in the short form, that will guarantee that 100% of the population will answer them, because they will also be in the long form.
In my opinion, these questions should be in the short form. I would like to hear you say that you intend to put them in the short form. I don't see what difference it would make.