Water leaving the spillway at the blowout is following a predictable path.
In figure 2 water to the left of the spillway runs roughly parallel to the spillway, takes a brief jog toward the spillway, and then moves progressively further from the spillway.
In figure 2 water to the right of the spillway runs roughly parallel to the spillway, bows sharply away from the spillway, and then returns to a roughly parallel course down to the river.
That's pretty much what happened:
Hi Ray76, FYI - Here's a superimposed photo of DWR's captured geologic 3D image data with your original topo map & stream denotations. There is an addition topographic inferred stream erosion path marked in blue arrows. This path follows the edge of the main spillway. Note: the 3D perspective image is rotated in the Z axis with respect to the topo map. This shifts a bit of the alignment references (such as historic roads).