Fallible rhymes with:
infallible, infallible, valable, appealable, available, billable, callable, consolable, controllable, gullible, incalculable, infallible, inhalable, inviolable, irreconcilable, noncallable, recyclable, resealable, salable, saleable, syllable, unassailable, unavailable, uncontrollable, unsalable, unsaleable, valable, violable
Fallible sounds like:
falafel, filippelli, filippello, flavell, fluvial, fulfill