The Samaritan text here reads:
I will go down now, and see whether they have done altogether according to the cry of it, which is come unto me; and if not, I will know. אֵרְדָה־נָּא וְאֶרְאֶה הַכְּצַעֲקָתָהּ הַבָּאָה אֵלַי עָשׂוּ כָּלָה וְאִם־לֹא אֵדָעָה׃
אֵרְדָה־נָּא וְאֶרְאֶה הך צעקתה הַבָּאָה אֵלַי עָשׂוּ כָּלָה וְאִם־לֹא אֵדָעָה׃
(The same substitution also occurs in 34:31 and probably elsewhere as well.) I presume, though, that this is just a way of indicating the same thing in Samaritan Hebrew: the principle meaning of הך, being the imperative of "smite", makes no sense here; nor does the other meaning in my dictionary, a (post-Biblical) Aramaism meaning "this" or "that". Often the variant words in the Samaritan text aren't in my dictionary (Klein's large Etymological Dictionary of the Hebrew Language, which I expect to have more words in it than my Bantam-Megiddo English-Hebrew/Hebrew-English dictionary or my Langenscheidt's Dictionary of the Old Testament— possibly Jastrow might have more, but Jastrow's irrelevant for Biblical Hebrew).Gen. 18:22 reads:
The men turned their faces from there, and went toward Sodom: but Abraham remained standing before the Lord. וַיִּפְנוּ מִשָּׁם הָאֲנָשִׁים וַיֵּלְכוּ סְדֹמָה וְאַבְרָהָם עוֹדֶנּוּ עֹמֵד לִפְנֵי ה׳׃
According to Jewish tradition, this is a emendation of the Scribes: The text originally said "the Lord remained standing before Abraham" (Rashi explains: because God had appeared before Abraham, not the other way around), but it was changed because it was felt disrespectful to have God waiting before Abraham for Abraham to finish his business with God. It's not clear who the "Scribes" referred to above are, but the implication seems to be the early Pharisees. So the question is: which variant will the Samaritan text have? What do you think?
And the answer is: The Samaritan text is the same as the Jewish one. Though of course whether this means that the Jewish text influenced the Samaritan one post-emendation, or whether the tradition that the text was changed, dating from over a thousand years later, remains an open question.
It's possibly worth pointing out here that when the Jews of the first millennium put their mind to remembering something, they did it well—an example is the Oral Law being maintained for centuries until it was written down—but when they didn't, they did it really poorly—an example being the causes of the revolt against the Romans that led to the destruction of the Temple, the mythical accounts in the Talmud and midrash having almost nothing in common with the contemporary historical account recorded by Josephus. On the other hand, I know of one instance where an account written in France in the twelfth century was later found to be substantiated by an account written (in cuneiform) in Babylonia, eighteen centuries earlier and two thousand miles to the east. Which goes to show, you can never be absolutely certain.
On the subject of Scribal emendations, there are twelve places in the Torah where words or letters are marked with dots, traditionally interpreted as having been put there by Ezra the Scribe when he was uncertain whether the marked words were authentic or not. Unfortunately my comparative chumash does not show the dots in either text, so I cannot know whether they are there in the Samaritan Torah too or not. As for the marked words, they are present in both texts, for at least the two locations I can think of to check off the top of my head.