You may be right about the OP's 'real' question, or you may not. Either way, the question needs editing.
It could say "Merriam-Webster says this, but Collins says, on the contrary, that"; which may be a fair SE question, but not one that can be guessed from the original. Close it and let OP ask what he really wants to know. ("May be" because I would hazard a guess that there is no word for which two apparently contradictory definitions cannot be found by mischievous or uncomprehending enquirers. Usually the problem vanishes on close inspection by native speakers.)
It could say "There appear to be two schools of thought on this grammar point; which is right?" Definitely not a question we want here; almost the definition of primarily opinion-based.
Or it could say "I don't understand how you form the possessive of a plural". There are so many duplicate questions already it wouldn't last five minutes; and more to the point, it would be bad for the site and bad for the questioner for us to explain a basic point that shouldn't be studied in isolation.
It is definitely not "up to us to clarify the reference work"; it is up to us to answer the question asked.
(I also agree with John Lawler that unequivocal referring to a source more usually means 'vociferous' than 'supported by evidence', let alone 'undeniable'. That's a more general point, though.)