First of all it's against Airbnb's T&Cs to accept third party bookings on personal accounts. If a company wants to do a booking for their employees they should use Airbnb at Work @Jessica2477
Have you found that Airbnb Help website - If not do bookmark it - it has FAQs around how to manage your STR business on Airbnb.
When the guest gave you stained bedding and other items the first week, why didn't you ask how this had happened, told her to stop using products causing staining and let her know if you couldn't get the stains out you would need to charge them for new linens etc.
If she lost the key it's a security risk. I would have at least asked for the cost of a replacement.
Of course you should leave an honest review and personally I would have charged for the key and replacement linens. You should mention that it was a third party booking and that the guest heavily stained linens without apology on two occasions and lost your house key creating a security risk. Wouldn't you want your fellow hosts to warn you about guests using personal accounts for work bookings and that the guest caused damage?