The evil counterpart to the Dwarves are simply evil Dwarves. Yes, Dwarves were not as corruptible as Men, and few ever directly served the forces of evil(referring, I suppose, to Sauron and Morgoth). But they were still prone to evil sometimes and committed 'their fair share of rash and greedy acts'(quoting wikipedia which I know isn't all that accurate). In general, the Dwarves of the Western Houses(Longbeards, Firebeards, Broadbeams) were on the good side, but the Dwarves of the Eastern Houses did get corrupted. According the the essay 'Of Dwarves and Men'(sadly, I don't have it with me now) they fell into evil and some even fought for Sauron in the War of the Last Alliance. Also, some tried to enslave Men in early days.
The Hobbit makes this clear.
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in some parts wicked dwarves had even made alliances with them
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and
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some are tricky and treacherous and pretty bad lots
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Note that in FOTR at the Council of Elrond Gloin says
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we knew already that the power that has re-entered Mordor has not changed, and ever it betrayed us of old
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indicating that the Dwarves were only friendly with Sauron.
Also, Gimli clearly distinguishes his Dwarf-House's status WRT Sauron
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My folk have never had dealings with any of the servants of the Enemy
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