@Aaron McCausland I've seen a slight variation of this same issue where it does transition, but then doesn't actually execute any of the actions on State B (even though the logs say those actions were executed). Have gotten them to investigate and determine it's some sort of unreplicatable network glitch. There's a SuiteAnswers (
https://suiteanswers.custhelp.com/app/answers/detail/a_id/95753/kw/95753) and a defect for it (Defect 417298: Transaction Management Problem in Workflow), but they've prioritized it U6 (aka they're never going to actually dig into it/fix it). So I guess all that to say, that yeah, very infrequently (once a year or so), some workflow will just fail to execute some portion of it (in your case the transition) and the logs will show it did do that action, when in reality it didn't. NetSuite is aware of the issue, but doesn't seem to think it's worth fixing, since we can manually fix things.
netsuite If you want to tag your support case onto the defect, that would help everyone, but it's been 3+ years with multiple occurrences (and tickets) with no movement, so I'm not holding my breath.