That knot would probably be ok if it was in the thickest portion of the handle, especially if you have a glues on riser on top of it.
I would definately not put either knot in any portion of the limb.
That 1/4" lam is straight enough for a backing ... I probably wouldn't use it for a belly lam. I'd buy an osage baord and rip it into 2 thin slats and make two tri-lams .... one BBO and one HBO, as always I love maple for the core .... just my two cents.
I don;t know who sells osage boards .... I think kenny M will sell osage lams that are thick enough for belly lams.
dunno the price, but figure $15-20 each or so for the maple core and the osage belly. You could get a tri-lam glued up with a $30-40 investment, plus they'd come already ground and tapered .... tough to beat.
or if you're set on hickory, go ahead and just use it for the belly. bea carefula nd trwap teh boo to help prevent chrysaling in the hickory.
Good luck and post pictures