am 99.999% sure I have seen people in wheelchairs near the touchline area at JS.
Probably home fans. The away section seems to taper into a small corner section, so maybe there was not enough space and protection for him.
Obviously it's ridiculous, because if you are designing an 'English-style' stadium a small 'walkway' for wheelchair access is pretty standard. The proximity of the stands to the pitch may be an issue, in this case.