Is there any valid reason that these prophecies do not entail future fulfillment when Christ returns as the scriptures attest He will?
There are at least two valid reasons.
1. Throughout Tanach (what you might refer to as the "Old Testament") there is no scripture that supports the notion that the Messiah will have to come twice.
2. In many instances, individual verses are picked out of context because one could look at it and say that it vaguely resembles what they think of Jesus.... yet many of the surrounding verses, especially those that contain the phrase "And on that day..." are lumped into a category of "oh, he'll do that when he comes back."
For example:
Isaiah 11
And a shoot shall spring forth from the stem of Jesse, and a twig shall sprout from his roots.
And the spirit of the Lord shall rest upon him, a spirit of wisdom and understanding, a spirit of counsel and heroism, a spirit of knowledge and fear of the Lord.
And he shall be animated by the fear of the Lord, and neither with the sight of his eyes shall he judge, nor with the hearing of his ears shall he chastise.
And he shall judge the poor justly, and he shall chastise with equity the humble of the earth, and he shall smite the earth with the rod of his mouth and with the breath of his lips he shall put the wicked to death.
And righteousness shall be the girdle of his loins, and faith the girdle of his loins.
And a wolf shall live with a lamb, and a leopard shall lie with a kid; and a calf and a lion cub and a fatling [shall lie] together, and a small child shall lead them.
And a cow and a bear shall graze together, their children shall lie; and a lion, like cattle, shall eat straw.
And an infant shall play over the hole of an old snake and over the eyeball of an adder, a weaned child shall stretch forth his hand.They shall neither harm nor destroy on all My holy mount, for the land shall be full of knowledge of the Lord as water covers the sea bed.
And it shall come to pass on that day, that the root of Jesse, which stands as a banner for peoples, to him shall the nations inquire, and his peace shall be [with] honor.
And it shall come to pass that on that day, the Lord shall continue to apply His hand a second time to acquire the rest of His people, that will remain from Assyria and from Egypt and from Pathros and from Cush and from Elam and from Sumeria and from Hamath and from the islands of the sea.
And He shall raise a banner to the nations, and He shall gather the lost of Israel, and the scattered ones of Judah He shall gather from the four corners of the earth.
And the envy of Ephraim shall cease, and the adversaries of Judah shall be cut off; Ephraim shall not envy Judah, nor shall Judah vex Ephraim.
And they shall fly of one accord against the Philistines in the west, together they shall plunder the children of the East; upon Edom and Moab shall they stretch forth their hand, and the children of Ammon shall obey them.
And the Lord shall dry up the tongue of the Egyptian Sea, and He shall lift His hand over the river with the strength of His wind, and He shall beat it into seven streams, and He shall lead [the exiles] with shoes.
And there shall be a highway for the remnant of His people who remain from Assyria, as there was for Israel on the day they went up from the land of Egypt.
The black bolded portion shows sections Christians have decided vaguely resemble their perception of Jesus.... ignoring the context of the whole chapter, and despite the indication that this is all regarding one subject (as pointed out in blue), Christians arbitrarily decide that the unbolded portion is simply future fulfillment.