You can try but it will not work. Arguably the award "should" not cost 70k if not all segments were available on the journey together.
I think the partner awards still operate under the older AA award rules.
While those awards permit adding/dropping segments, they cannot change the award type. India to Europe and India to North America are different awards so wanting to combine them to take advantage of lower pricing would require cancel/redeposit/having the same inventory available for rebooking.