Yes they will lie. The trick is you ask them first "what have you tried so far", they are all to willing to let you know they sprayed (read that here a few years ago and it works). I don't tell them why but I do not take the job.
You can usually tell if they have been sprayed recently from dead bee in the bottom of the cavity. If there was no sign of dead bees and the right amount of bees for the size of the hive. I would feed it back and keep an eye on them.
If it was not capped it may have had excess moisture and started to ferment, you can check this by sealing your honey in a glass for a few days/week when opened it should release gas.
Some honey can have strong tastes. Those make some good mead.