Purge Valve sticking

[Truckdriven]

Got a 2020 KW T680 X15 590k mi. with a Bendix AD IS air dryer and the the purge valve stuck open one day. Pulled the purge valve out and it was all plugged up with black gummy stuff (see pic), I would blame it on egr soot junk but it has the N/A Air compressor. I'm thinking air compressor may be pushing oil but wondering why it is so gummy and almost burnt looking? Is it possible the coolant isn't circulating or cooling properly in the compressor? The entire air dryer assembly was replaced 60k ago in April by the previous owner because it wouldn't build air properly so pretty obviously the same root problem. Just wanted to get some input on this before I replace a compressor??