I see what I did wrong, and it was code I omitted from the ticket.
ignite.events(ignite.cluster().forCacheNodes(cacheConfig.getKey())).remoteListen(locLsnr, rmtLsnr, EVT_CACHE_OBJECT_PUT, EVT_CACHE_OBJECT_READ, EVT_CACHE_OBJECT_REMOVED);
When it was trying to register this code twice, it was causing that strange error.
I put a try-catch ignore around it for now and things seem to be ok.
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