Someone who is more au fait with the sources may have an answer The ultimate WP tests are verifiability and reliability But verifiability takes precedence in my opinion It can lead to daft results where something which might be true cannot be verified but something which is not true can be verified  one has a reliable source the other one is for example just plain old common knowledge  On the odd occasion that Ive hit the sort of mess you mention above and in the absence of a source to prove one way or the other Ive tended to present all the possibilities But this is dangerous territory you are admitting to a potential discrepancy good because the new reader is then aware that the article appreciates a possible anomaly but potentially inviting comments about original research bad according to WP policies  Hopefully someone with more experience  either in this subject or in WP policies  can resolve the issue In the interval keep calm and carry on