if u tell 公司hire了一个骗子 = hire Mgr and HR is dumm

The hiring process usually is:
HR do the screening, then onsite interview, then the hiring manager make decision.
Now, they think they are smart hired a good candidate.
If somebody tells tham that this good candidate may not that kind of good, that means, hireing mgr and HR (who did involve the hiring process) are dumm.

Then you know what will be the result....
Enjoy your life...
Thanks!