I am a Speech and Language therapist and have had the same conversation with my SENCO at school. These children need to have either functional or entry level in order for them to succeed. It shouldn’t be about Ofsted, it should be about the children. And what is the point of them going GCSEs where the work is not accessible for them. If you can justify why they are doing alternative qualifications, and what it will lead to for them, then keep your argument going with the Head. Ultimately if they get a grade 1 in the GCSE, they will still have to go onto an entry level course at college as they wont be able to access Level 2 or 3 so why not give them easier options to build confidence and let them gain something which is meaninful, not just a piece of paper.