Azumarill with Aqua Jet is a danger to this mole. All Doryuuzu I've faced online have been OHKOed by CBAzu's AJ, considering Huge Power, and with some relative bulk the rabbit can take neutral moves from it. After a Swords Dance, however, he's OHKOed by Earthquake which puts a damper on him.
I'd go as far to say that Azumarill is one of the best checks to Dory around.
honestly there are so many other pokemon that check doryuuzu just as well, if not better, than azumarill, that it isn't really an exceptional check imo. technician breloom with mach punch shits on doryuuzu all day, and basically anything with priority will be a huge problem for the mole. i've been hearing a lot of players complaining about how "broken" and "hard to beat" doryuuzu (specifically swords dance doryuuzu) is, but in actuality all you have to do is pack a super effective priority user like breloom or a physically bulky mon like hippowdon. hell, you really only have to change the weather to completely neuter doryuuzu. while he is really fun to use and no doubt powerful, he certainly isn't unbeatable. he does usually take out at least one pokemon a match, however, but his frailness means he isn't tough to revenge kill.