@Ian0, we are all in this predicament because Airbnb relies heavily on guest review, as our future bookings also do. It is unfortunate, yes, but it's their way of giving the benefit of the doubt, which is where you stand with your cleaner (and your guests); hence, your so-called "overanalysis" is understandable and justifiable because you want to give the best for both. However, based on my experience, unless you check the house condition yourself, you will almost (sadly) can never rely on the guest's reviews nor your house cleaner.
To add to Helen's (of Bristol, UK) remarks, you will have to embark on a "trust" journey, which can be unsettling if the guest's and the house cleaner's reports do not match, as you have just experienced.
It is annoying indeed, especially now that Airbnb does not provide that detailed information to hosts anymore. It puzzles me why they (Airbnb) would take away the tools that hosts can use to aid in their hosting, rather than help them.
As for guests who give untruthful reviews, Carol (of Lombard, IL) made a valid point, as I've many first-hand experiences. This is the reason why having a "strict cancellation" policy comes in handy, as there those who are not used to always telling the truth:
- There may be some guests who would "prey and capitalize" on the host with a bad review and use that info to fabricate a sob story to get their money back. I have had an instant book guest in 2016, who said, and I quote, "It's okay, I can just call Airbnb and ask for a refund without you getting affected," as they walked away despite my encouragement for them to stay. Though one can be thankful for this guest's honesty to a host, I was shocked hearing that, because this business is based on "honor system."
- The fabricated bad reviews may affect your future bookings, especially from guests who (literally may) rely on them. I had another guest who booked at least 9 months in advance and cancelled a few weeks prior to arrival. Two months later, I discovered that the guest actually stayed at my neighbor's instead; hence, lied about the reason for cancelling.
- Most guests will not give you the 5-star rating you deserve if your house is not "dressed in a luxurious" (expensive) furnishings, even if the host meets the 5-star ratings on the definition of each of the 6 categories: cleanliness, accuracy, value, communication, arrival, and location.
- The 7th category, "overall," is where Airbnb bases the host rating, which in itself is unreliable, because this "overall" category will be impacted if the guest had encountered bad experience(s) somewhere along in their travel that does not have anything to do with your hosting or with the accommodation.
Side Note: I have spoken to Airbnb several times regarding these inaccuracies, and the reply I got was we should "...not worry because other guests will give good reviews and it will all balance out." What that Airbnb employee failed to realize is that it takes a long time (not shorter than 3 months) to bounce back from even a 3-star rating. We can only hope that future guests will see the truth amidst the lies.