Decomp tube replace or not?

Got a couple codes that lead me to believe I was about to get epa'd. Started by trying to remove the def doser but broke a bolt. Since that happened I went ahead and removed the decomp tube and found the buildup.

If that def caked up able to be removed and if so what's the best way? How about removing the broken bolt from the def doser since that has to be replaced as well. Any tips or tricks on that because it doesn't look easy?

 

The doser is getting replaced for sure if I can get the broken bolts out and clean up the def. Will check the downstream to make sure there isn't further contamination.