I have been dealing with this exact situation towards the end of last season and was thinking of posting it here.
During last season I observed four instances where there were forward passes into touch. Three were L4 and one at L6. What the ref did varied. One offered an option. One gave a lineout and two gave a scrum.
The Laws since the 2018 ‘simplification’ doesn’t provide for an option. They did in 2017, (Law 12) There is a suggestion of an option in the grid for when to award a scrum.
The reason for the ‘confusion’ I would suggest is that we are now getting referees coming through the levels that were not refereeing prior to 2018. That was the case in my observations.
As a result of my observations I raised the matter with RFU Laws. There was agreement that there is now some confusion and the question of tweaking the laws to avoid this and to get back to the 2017 situation was put to WR. They responded by saying that it would be an item on the law revue This year. I was told that this usually takes place in August.
I am waiting to see if this is going to actually happen.
The expectation is that there should be an option as per 2017. Every referee I have seen who has been refereeing since before 2018 gives an option. Until I made these observations I also thought I was incorrect After checking the ‘simplified’ laws.