1)
Why did he ask "u'Mah La'asos li'M'as ha'Kikar"?
1.
Metzudas David: Should I lose the money? They will not return it to me!
2.
Malbim: If one hires a worker, and after the worker goes to the worksite the employer retracts, if he was negligent, he must pay him like an idle worker (a discounted wage that he would consent to receive and not work). If he retracted due to Ones, he is exempt. This is Ones, for I did not expect a Navi to make me retract 1 ! If so, they should return the money to me!
1
Seemingly, this is negligence. He should not have relied on help from Resha'im. Yehoshafat was punished for joining with Malchus Yisrael! (PF)
