That crank is unusual and therefore it is hard to give you advice.
It shouldn't be the bearings because they don't usually make a big noise, but rather make the crank harder to move around (you can perfectly feel bad bearings if you try moving it with your hand and feel resistance/side-to-side movement).
Can you install the crank without the clutch mechanism, or simply install another crank, and test if the noise goes away? My bet is it will :)
If the noise goes away, the best is to contact Giant support or a representative and see what they can do for you (send you new pieces, help troubleshooting, etc). If they can't do anything for you, at least ask them to advise on a solution, or to suggest a list of cranks that are compatible with the electric system, in case a normal crank does not work.
While testing keep in mind this can be a malfunction piece which might fail to perform inat the worseworst possible moment, so keeptake it easy. Good luck.