In physics one significant view of space is that it is a relationship
between 'objects'. But since 'a person doing imagining' is axiomatically 'a subject' contemplating 'objects', Kant's reference to 'imagining' by a person is tautologically correct with respect to the concept of space as an a priori
. It is only when we take a metaphysical (holistic) view of existence as a seamless continuity between what we call 'subjects' and 'objects' that 'space' can be transcended.
Apologies if anybody has already pointed this out above.