I do not agree with you that there is no historic fulfilment of either Isa 17 and 19. Damacus was taken by Tiglath-Pileser III between 738 and 732BCE, and Egypt was invaded by Esarhaddon, all these events are recorded on ABC 1 (BM 92502), as well of the sacking of Babylon by Elam in 694, which makes Isa 20 refer to this even and not the later defeat by Cyrus.
Just show me the scriptures that refer to these specific people, events and dates and I will agree also.
Viviane - Are we restricting the use of a post written prophetic/ History or did you rule that out in the OP?
I don't understand what you mean.