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What do you mean by "primary domain"? Are you talking Google Search Console or something else? I assume you are not using the other domains other than to redirect? Let me know if the above is true. You can move to yet another domain, but it is advised against as EffectDigital said because everything has to be reindexed again. It's possible to do and they'll be fine in the future, but it is going to hurt for some time.