Engine break works intermittently

I was at a Love's getting service recently. They mentioned there was an emissions related recall on the 2023 Cascadia I'm driving. Our maintenance departments as well as a few diesel mechanics have told me in the past that there was no fix for this recall. I have a check engine light. When the code is pulled it points to this recall. A few weeks ago the engine brake started doing something weird but I don't know if it's related to the recall or another matter entirely. A separate check engine light as well as the adaptive cruise and active brake assist malfunction lamps all lit up at the same time on the dash. The RPMs would rise like the engine brake was trying to work but the vehicle was not slowing at all. Had to watch my speed and use the service brake at times to slow the vehicle when going down hills. These same malfunction warnings also pop up at random while driving down the road (with and without the engine brake being used). Any thoughts on this?