we use successfully for the oocyte activation the calcium ionophor (Cult-Active medium Gynemed). See:
Tejera A, Mollá M, Muriel L, Remohí J, Pellicer A, De Pablo JL.: Successful pregnancy and childbirth after intracytoplasmic sperm injection with calcium ionophore oocyte activation in a globozoospermic patient. Fertil Steril. 2008 Oct;90(4):1202.e1-5. Epub 2008 Mar 21.
Ahmady A, Michael E.: Successful pregnancy and delivery following intracytoplasmic injection of frozen-thawed nonviable testicular sperm and oocyte activation with calcium ionophore. J Androl. 2007 Jan-Feb;28(1):13-4. Epub 2006 Aug 9.
there exists an experimental work describing the oocyte activation using the recombinant PLC zeta, but I did not read any clinical article describing them. The experimental one is:
Nomikos, M. et al. (2013) Phospholipase Czeta rescues failed oocyte activation in a prototype of male factor infertility. Fertil. Steril. 99, 76–85.