The pilot in question is a student and is undertaking a formal course of training which has been specified by his school. It is illogical that an ab initio student with say 7-8 hours flying experience can be authorised solo but a lapsed PPL (licence also lapsed) with perhaps hundreds of hours experience, under the supervision of an ATO, cannot be authorised solo as part of his/her training. The night rating specifies the solo element. Holding a licence is an administration process to enable the attachment of the night rating. A joint application therefore is possible.
The law is of course a different matter and cannot be assumed to follow logic. As has been said we need a reference. An ATO will quite reasonably expect to have certainty that they are doing the correct thing.