I don't belive Fatality would have any issue with pulling 100s to a prep or a fullot, and as all know Fatality did have the possibility to pull in 5 more people into the portal, or even enough to outpull Apex.
The issue is the elitist side of it all, both clans want their best P2P warrers to perform as good as possible. This does not only go for Fatality, as we have seen the same behaviour in apex, i.e if you don't perform well in inners you cannot attend. Nothing strange about this.
If FI has 45 people who are ready to fight, I don't see the reason for Apex not willing to sit those 5 people, even when it is stated in the rules, unless they want to avoid.