He can write illustrated statements about the 'olfactory elements' of his work.
He should absolutely include his printmaking, and show he has a knowledge of it, especially if he has an interest in clothing.
If has an interest in textiles generally, show it.
He could be said to be blending fashion as function, with fashion as visual aesthetic from a fine art perspective.
If the end result is attempts to push him towards fashion and textiles, remind him that fine art is a broader church in which he can do everything and anything at the right university.
What you've said suggests he's interested in the viewer experience and arts relationship with it's audience, so a bit of looking into interacting with multiple senses and being able to talk about that, should carry him well.
Look at the relationship between the display of any item of art and instillation art.
Imo showing as broad a range of work and interest rather than 'here's my great finished pieces' is the way forward, (but don't cram in everything but the kitchen sink.)
Where he's applying may influence what they would like to see.
But what most want is to see someone who wants to develop, wants to try everything, is open and keen, and is going to turn up a lot, (big issue these days) and being passionate never hurt anyone's chances.
A visual montage of who and what inspires him can be a really useful talking point, but he needs to make sure he is then able to talk about them and why, - some students pick specific artists because they think others will be impressed by their choices and sophistication, it isn't what's being looked for.
However some specific (mainly London) places tend to have a 'house style' that they seek to mold students to, and if he's headed for those then research is his friend.
Personally I wouldn't encourage him to look at anywhere that doesn't encourage developing his own interests and style, especially at foundation level. Ask them how broad a church they are when choosing - he should choose them as much as them choosing him.