Is there an alternative to GetTargetIsotope with NeutronHP?

Hello, everyone,
I am now studying neutron (with 1000m/s) elastic scattering on a experimental setup as background events.
I would like to get target isotope Z and A when hadElastic occurs.
But using NeutronHP, G4HadronicProcess::GetTargetIsotope() only returns null pointer. (as written in example of extended/hadronic/Hadr03/src/
Is there an alternative method to GetTargetIsotope with NeutronHP?
Of course, I can estimate with a boring calculation using the information of post step material and cross sections…

Thank you in advance,
Go Ichikawa