What all this adds up to is that even leaving the moral dimension of the act aside, from a purely pragmatic perspective, reblogging that callout post accusing a random trans woman you've never heard of of being a dogfucker or what-have-you is an action which, in a worst-case scenario, will contribute to ruining an innocent person's life, and in a best-case scenario, is likely to accomplish nothing whatsoever.
Folks often justify reblogging callout posts without performing due diligence under the rubric of "better safe than sorry", but any realistic assessment of the likely outcomes will tell you that the true "better safe than sorry" course of action is to keep your damn mouth shut!