That is an interesting issue. However, there is another technique to create cloned mammals that has is used industrially to create non chimeric mice from embryo

That is an interesting issue. However, there is another technique to create cloned mammals that has is used industrially to create non chimeric mice from embryonic stem cell cultures. A donor blastocyst is used as a host. At a particular stage of development, implanting a number of ES cells from the desired clone into the center of the blastocyst induces the donor blastocyst to develop into the placenta, while the ES cells continue development as the fetus. This allows for engineering of the ES cells independently, without failure prone nuclear transfer. It would be interesting to know if this would work in primates. It may be difficult to maintain the ES cell cultures. It might also be riskier in some sense. I'm curious what others know about this.