I am saying that nothing in the words attributed to Jesus about the Memorial specifically say that wine is to be used. As to whether or not fresh grapes and fresh grape juice would have been available during Passover time, I don't know, though I know the WT says such was not available. Regarding the account of Jesus turning water into intoxicating wine for the guests to drink, such is somewhat unsettling to me whenever I think of that account. I don't know what to make that account regarding the wine mentioned as being intoxicating. I have not done much research on that matter, however the https://www.ministrymagazine.org/archive/1965/02/wines-of-the-bible source I provided in my prior post briefly discusses an SDA view about the turning of water into wine and about the meaning of the biblical words which are sometimes translated as "wine". That source also says the following.
'Christ's first miracle at the marriage feast was to produce "good wine" in an emergency. This was the pure juice of the grape.
... The Saviour's final act with His disciples was the institution of the Lord's Supper to take the place of the Passover supper. That the wine used on this occasion was unfermented is established by the fact that during the Passover season leaven and all other things fermented were not to be found in any Hebrew home (Ex. 12:15). It is unthinkable that the wine used to represent His blood (1 Cor. 11:25) would bear the taint of ferment and its cause, which is death. Jesus said to the disciples, "But I say unto you, I will not drink henceforth of this fruit of the vine, until that day when I drink it new with you in my Father's kingdom" (Matt. 26:29). The wine used at the Lord's Supper was called the "fruit of the vine." Ferment is a type of sin, and since in Him was no sin, the wine that represents His blood must be without ferment.
... The Septuagint uses the Greek oinos to translate both yayin and tirdsh—the former referring to wine in general, the latter to unintoxicating wine. On the basis of this, careful scholarship should attend the interpretation of those texts where oinos is used, taking cognizance of the context in which the word is found. This alone determines whether oinos should be rendered as an intoxicating beverage or not. Notice the usage of oinos in the following texts: Luke 7:33—"For John the Baptist came neither eating bread nor drinking wine; and ye say, He hath a devil." Luke 10:34—"And [the good Samaritan] went to him, and bound up his wounds, pouring in oil and wine." John 4:46—"So Jesus came again into Cana of Galilee, where he made the water wine." The word oinos is used in each of the above texts, but obviously different kinds of wine are being set forth.
... The study of the wines of the Bible reveals the fact that for every
good thing that God has made, Satan has made a counterfeit. Nowhere in
the Scriptures can it be proved that God has put His endorsement on the
use of intoxicating wine. He has given man the pure juice of the grape
for his enjoyment and benefit. He provided it as a symbol of the spilt
blood of Jesus Christ for our sins, and greatest of all, we have the
Saviour's promise: "I will not drink henceforth of this fruit of the
vine, until that day when I drink it new with you in my Father's
kingdom" (Matt. 26: 29).'
If I recall correctly, Charles Taze Russell did not alcohol. But his successor, Joseph Rutherford (a drunkard) did. Rutherford published considerable literature through the WT saying it is fine to drink alcoholic drinks. Rutherford resisted the Prohibition amendment to the USA Constitution which prohibited alcoholic drinks. On the matter whose views was more correct - that of Russell or of Rutherford and the successors to Rutherford?