He is making a fundamental error. The text in Heb 9:16-17 refers directly and specifically to the Sinai covenant.
According to covenant practice in ancient Israel, parties who enter a covenant swear an oath that invokes a curse upon anyone who would dare to violate the covenant. This is precisely what Israel did at the foot of Mount Sinai when the nation entered its covenant with Yahweh. The ratification ceremony, which involved the slaying of oxen is a symbolic blood ritual, was a visible sign of the oath curse, signifying that Israel chose to accept the same deadly fate should it break the covenant. So, as soon as Israel betrayed the covenant at Sinai, falling down in worship before the golden calf, they placed themselved under the curse of death. However, instead of activating the full force of the curse then and there, God mercifully allowed Israel to live and instituted the annual Day of Atonement. He did this to hold the curse of death at bay until the time came when He would deal with the transgressions of his people in a difinitive way.
This is what Heb 9:16-17 is talking about. Paraphrased it reads: “Where there is a covenant (like the one made at Sinai), the death of the (unfaithful) covenant partner must be endured (once it is broken). For a covenant is confirmed (as being in effect) when death occurs, since it is never in force when the (guilty) covenant partner is living.”
The author is explaining how Israel, despite being guilty of transgressing the Mosaic covenant, was spared the curse of national death it had invoked upon itself. Instead, Jesus took this curse upon himself, finally putting the sanctions of the Mosaic covenant into full effect and bringing it all to an end.
For this reason he is mediator of a new covenant: since a death has taken place for deliverance from transgressions under the first covenant, those who are called may receive the promised eternal inheritance. (Heb 9:15)
Like I said before, he is making a fundamental error. The curse of death was not held at bay until Pentecost. It was held at bay until the death, resurrection, and ascension of Christ.
For Christ did not enter into a sanctuary made by hands, a copy of the true one, but heaven itself, that he might now appear before God on our behalf. Not that he might offer himself repeatedly, as the high priest enters each year into the sanctuary with blood that is not his own; if that were so, he would have had to suffer repeatedly from the foundation of the world. But now once for all he has appeared at the end of the ages to take away sin by his sacrifice. (Heb 9:24-26)
I hope that helps.
