While I respect that intelligence of this sort may need to be kept secret, Trump also bypassed Congress in his decision, no one that I'm aware from the IC has endorsed Trump's claim, others have reported conversations with said folks who suggested evidence was not significant of this, and the option to go after Soleimani was reported to be offered to make other approaches seem more appealing without expectation of Trump pursuing it. Compiling that with Trump's history of rampant dishonesty and undercutting the IC, I really can't find a reason to believe this claim absent presentation of evidence or accounts from those outside of Trump's direct command.