Using powers of tau setup parameters for KZG10

[cmrfrd]

I'm interested in seeing if it's possible to leverage the powers of tau as they exist in the zcash downloads for constructing the reference string needed in KZG10.

KZG10 is constructed via pairings meaning it needs a reference string in bls12381 G1 and g^alpha in G2.

After speaking with @ebfull the G1 portion can be extracted from the h parameter here, but the question still remains as to where / how to extract g^alpha in G2.

Any insight would be greatly appreciated