While unlikely, it is possible ...
You need to just pencil that into your chart and then do your own research, just using that as a "possible".
I had one on my tree where I couldn't believe that my GG-gf had married a particular lady. I had no clue where the online tree got that name from. I could look up the marriage on LDS and see it, but that gave me no clues whatsoever that it was right ... I even got the banns, still nothing there to give me a clue - and, finally, I found the evidence myself ... if I'd just dismissed it offhand without pencilling it in as a maybe I might've completely forgotten to continue looking/checking. I'd have forgotten what I saw that day, just because I'd presumed they'd made it up due to laziness and "because the first names fitted and were in the right county".
Pencil. Sigh. You'll find evidence once day one way or the other.