Routing the junction North would lose significantly more land, especially taking into account the need for the new road to meet the North/South road at 90 degrees, rather than an acute angle if the new stretch were completely straight.
According to this Highways Guidance
, the reason for preferrring right/left staggers is not because of any difference in safety at the first turn:
Right/left staggers are preferred to left/right staggers because traffic turning between the minor roads is less likely to have to wait in the centre of the major road
That is largely irrelevant in this case, because the North/South traffic levels are very low. Consequently cars are unlikely to need to wait to turn right, and even when they do it will not cause a significant build up of traffic behind them.
I would have thought that the proposal would deliver the much needed increase in safety, even if it was not possibly the ideal solution. This is probably a case of not letting the perfect be the enemy of the good: getting the Verderers to agree to this is probably going to be difficult anyway.