I’m not sure of what you are trying to achieve, but palabos recently added the partially saturated bounce-back implementation (see https://gitlab.com/unigespc/palabos/-/merge_requests/67). In this scheme, some nodes operates a mixed full-way bounce-back, and fluid collision. This method seems a more convenient starting point than the half-way bounce-back if you want to mix together different dynamics. Maybe you can start checking how it was implemented looking at the merge request and start implementing it similarly.
Otherwise, can you give some more details/reference on the model you want to implement? Especially if you really think it is necessary to use the half-way bounce back.