Brown pleaded guilty, but his legal representative argued that it should have been a mid entry point, so a 3 week ban. The panel disagreed and decided it was a high entry point due to the dangerous nature of Brown's actions even though they agreed with him it wasn't deliberate.
In all honesty, it was more luck than judgement that Brown didn't stamp on Tommy's eye, so I don't think he can argue it wasn't extremely dangerous. A different panel may take a different view on the deliberatness of the offence, in which case the ban may be increased. In that case it'll be increased