They might exist, but I can't find them and don't recall seeing them. Hopeful I haven't missed a whole bunch of stuff I'm supposed to be applying this year :chin:
I think you've been sold a Furphy about the training slides.
There are no Guidelines/Slides/Videos from WR regarding the situation in the OP.
The videos and guidelines re the ref calling for a team to "Use it" is when the opposition choose not to engage the "maul" at a lineout and the team in possession move the ball to a player further back in the group. In that situation the ref will call "Use it" and failure to do so results in a turn-over scrum. I think the poster who thought there were slides etc, may be getting it confused with the scenario I have just described.
As for how the ref handled it in the OP, I believe he was correct and is backed by the term, "for any other infringement/situation??? not covered in law, a scrum will be awarded to the team in possession or the team going forward or the attacking team" (my wording. I'll go look for a Law reference)