10 min dishonor for a dc
Same sort of thing happened to me, the Guild Wars 2 client hard froze on me I had to manually restart it. I immediately re-entered the match but it was just ending.
Counted me has having abandoned the match and gave me a dishonor timer.
Difference in my case however is that I wasn’t having network issues (I check it and my connectivity was fine) yet still the game assigns punishment as if I’ve dropped out of a match in purpose.