Such suspicions might not amount to much in the eyes of the masses or those not too privy to the matters of the military, like the majority of the nobles who led the country. But Farhad was none of those. He knew that something was going odd.
'Royals can't be trusted.' Although his interaction with Jester has been little since he heard his voice again, Farhad still carried all those memories that had played a huge role in affecting his view on life, as well as death.
His hatred which was only small and based on suspicions has only grown stronger with time. Not to mention, that legendary being sealed beneath the city.
His warnings, along with the rest of the stuff he had experienced first hand didn't leave a good taste in Farhad's mouth.
If not for Rudrain, he would have directly raided Amir's research lab and threatened him to answer the truth. But the capital made things a bit different.