Dying Marionberries - dark blotches with white blob
Lane County Oregon
There are probably a couple things going on here. The reddish lesions are probably a common fungal disease called Purple Blotch - here is some information - http://whatcom.wsu.edu/ipm/manual/black/purple_blotch.html
However, the Purple Blotch alone probably would not cause the canes above the lesions to wilt & die. There is a possibility that this could be the result of the Rose Stem Girdler, a small coppery, metallic beetle that is becoming more common in the Willamette Valley. It normally lays eggs on the bottom third of a cane. Then larvae bore directly into the cane, resulting in wilting above this area in mid-summer. Recommend that you cut the effected canes just below the wilted portion and keep cutting to see if any larvae/other pest is present.
Here is information on these beetles - https://pnwhandbooks.org/insect/small-fruit/blackberry-raspberry/blackberry-raspberry-rose-stem-girdler
Then, it is strongly recommended that you remove and burn (or dispose in the garbage) any effected canes. This may help reduce future populations.