Correct is "Věřil bys ..." = future time. "věřils" = past tense, but "věřils by" does not make sense.

It appears that you may have something specific in mind. We would appreciate it if you would indicate why you believe this word order is inappropriate. To help us fully understand your position, please also indicate what word order you believe should be shown above as the main translation, and why. Constructive comments are much appreciated.