Those are the proposals, yes. OP states the following:
RBR was recently accepted as a 5D Low 1-C structure in the CRT linked in Planck's OP.
RBR is confirmed by the Cookbook to be actually part of Yggdrasil itself, formed by the Yggdrasil's branches. As such, the tree itself would be Low 1-C as well.
The Light of Alfheim transcends the 9 Realms and keeps the Nine Realms separate with its power, and it has to permeate the Realm Between Realms to do so. As it permeates through the 5-dimensional void (in this case the RBR), it is also a 5D Low 1-C force. The Light of Alfheim is also merely part of Yggdrasil.
Surtr was able to damage the Yggdrasil by using Primordial Magics stemming from the Void of Ginnungagap and the Primordial fires from Kratos' Blades of Chaos. When Kratos says his blades are not of Norse origin, Surtr replies that it shouldn't matter, confirming that Primordial Magics are the exact same and equal in potency regardless of their pantheon of origin. Magic as a whole sustains pantheons and without said magic, Pantheons collapse and die. As a result, all Magic would similarly be of 5D Low 1-C potency.
OP goes into detail a lot more with the fundamentals, but this represents the end result just as well as OP.