Follow the argument carefully in Hebrews.

According to the elaborate analogy that is being developed Jesus becomes a high priest at the resurrection. This is apparent from 5:5-10; 6:20; 7:15-16, 20-21, and the allusions to Psalms 2 and 110. He is therefore not a high priest when he is killed - he is made a high priest forever because of the obedience that led him to suffer (5:8-10).

As the resurrected one he is seated at the right hand of God; as high priest he is a ‘minister in the sanctuary’. The writer to the Hebrews fuses these two motifs (8:1-2) and presumably did not regard the fusion as incoherent.

When the high priest enters the inner tent he brings an offering - the blood of an animal previously killed - for his own sins and for the sins of the people (8:3). This is where the confusion arises in your argument: the animal is first killed (corresponding to Jesus’ death: cf. Hebrews 10:14) and then subsequently its blood is offered by the high priest in the sanctuary. So when Jesus first enters the sanctuary, when he first appears in the presence of God (not the throne language here), he brings as an offering ‘his own blood, thus securing an eternal redemption’ (9:11-12).

So the order of events is as follows: Jesus died, he rose from the dead, was exalted to the right hand of God, was appointed as a high priest forever in the heavenly sanctuary, and entered into the inner tent with the offering of his own blood for others, as the ‘mediator of a new covenant’ (9:15). This is Jesus’ first appearance in the sanctuary, in the presence of God; it served to ratify, in effect, this new covenant for the forgiveness of sins and opened up a way for believers to enter into the presence of God (cf. 10:19-22).

But the writer then says that there will be a second appearance in the sanctuary, not to deal with sin but ‘for those awaiting him for salvation’. This is clearly a salvation that those waiting do not yet have: an ending to their suffering and uncertainty. But as an appearance in the sanctuary it is like the first appearance in the sanctuary: both are events that take place entirely in heaven, neither involves a coming to earth. The passive ophthÄ“setai describes a heavenly vision, much like the passive ōphthÄ“ in Revelation 11:19.

This second entry into the sanctuary corresponds to the coming of the Son of man to receive a kingdom, to the vindication of the suffering saints. It emphatically does not refer to a second coming of Christ to earth. That completely misconstrues how the writer uses the high priest typology.