The ‘at best’ was acknowledging that. The Saudis have 11 years to find a compromise - or at least pretend they will find one - which can then be abandoned once everyone is in situ.
It'll be interesting to see whether FIFA lose control of the tournament in the unprecedented manner that they did in Qatar. Promises there about the availability of alcohol at the stadia weren't kept. The organisers just made sure they left it so late that FIFA could do nothing about it...