We moderate in different ways, for example, every user using our latest apps can flag a report to CE admin for us to take a look at, and we do. If we find something wrong we remove the report, if a user has made say 20 reports and they are all like "Rapist" or "Thief" etc and they are the only ones to report this, we may decide the user is making fake/false/embellished reports, and remove the reports & their access to CE. It's a balancing act
To give a further example, yesterday we had 2 reports made within 2 mins of each other, one said he arrived and tried to "haggle the price" the other said "Removed condom", both cannot be true at the same time (unless its the same user using 2 devices to report which is also not allowed). Things like this will always be looked at and the user's future reports will be monitored more closely.
We can never eliminate singular false/false reporting but we can do our best to discourage it and can act if a user is found doing so.