Replacement Referee

[Gomes]

In the quarter-finals of the World Cup, a very rare injury to a referee occurred in a test match.
Jaco Peyper referee's of the game injuried in the match.
Apparently in the quarter-finals WR selected assistant referees as replacement controller/fourth official.
In the Wales game against Argentina it was Australian Jordan Way.

 

[crossref]

It will be AR1 who takes over, and the 4th official takes over from AR1

 

[Gomes]

Yes. Karl Dickson (AR1) became Referee and Way became replaced assistant referee in Dickson's spot

 

[SimonSmith]

Karl Dickson:

 

[DocP]

So did Jaco head to the sheds or does he take over 4th official duties? Presumably there isn't an unamed individual who steps in to manage substitutions and yellows etc?