Gellerpox and rogue trader unit valid in 9th?

[angrom]

Hi all.
I am wondering if including a detachment of gellerpox is still legal in 9th matchplay?
I know that the specialists detachment are not legal if I remember correctly but I cant remember about the gellerpox supplement.

[N1SB]

I flipped through Codex Gellerpox Infected right beside me.  Here is my honest understanding.

 

It is still legal to include a detachment of Gellerpox Infected.  The reason is the Codex is still allowed.

 

Gellerpox Infected are NOT a Specialist Detachment to my understanding, it is just a really small Codex.

 

Their Faction Keywords are: Chaos, Gellerpox Infected.  I believe any army that includes them breaks the mono-faction (even, say, Death Guard or Nurgle Daemons, because it's specific to Gellerpox Infected), thus everyone loses their mono-faction special rules.

[Closet Skeleton]

9th ed matched play isn't a single thing unlike 8th.

 

In 9th matched play means 'according to a mission pack'. Its the tournament mission pack that bans specialist detachments, the Eternal War mission pack in the big rule book does not.

[Sword Brother Adelard]

Crusade also bans specialist detachments.