If your not sure about them being accurate for a match I wouldn't accept the merge I would however put a note on the profile to state such facts we however do not want 2 separate identities to become conflated.
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I say merge them. There is no data- only a name. It is conceivable it could be spelled like that at some time. It will likely remain as is forever - no benefit to anyone. Just put in a research note: It has been suggested the LNAB is spelled Brashear, with no sources provided.