ok do this
goto the pfblockerng config screen
at the top area you see sections, last but one is logs, click it.
Then click dnsbl.log in log file/selection
You should see the info you need, e.g. I tested on a domain just now and here it is in that log.
DNSBL Reject,Jan 05 21:47:52,003-pc.ru,192.168.1.124, | / | Mozilla/5.0 (Windows NT 6.3; Win64; x64) AppleWebKit/537.36 (KHTML like Gecko) Chrome/55.0.2883.87 Safari/537.36
DNSBL Reject,Jan 05 21:47:53,003-pc.ru,192.168.1.124,http://003-pc.ru/ | /favicon.ico | Mozilla/5.0 (Windows NT 6.3; Win64; x64) AppleWebKit/537.36 (KHTML like Gecko) Chrome/55.0.2883.87 Safari/537.36
it doesnt tell you the dnsbl list tho, which might be why its advisable to split lists into their own dnsbl feed aliases so you know from the counter which list it hits.
I am using malwarepatrol also via dansguardian feed, for that one you definitely be advisable to whitelist alexa top 1k sites.