Why does the Rashbam (d"h "v'lo" on daf 99b) have a different order in the four l'shonos geulah than Rashi (sham, d'h "arbah kosos")?[Rashbam's order is "v'hoztaitzi", "v'gaalti", "v'lakachti", and "v'hetzalti", whereas Rashi's order, which is the more 'traditional' one and is in the order of the p'sukim [see parshas V'arah, {Shmos} 6,6-7]is: "v'hoztaitzi", "v'hetzalti", "v'gaalti", "v'lakachti".]
Good point, why is v'Hitzalti listed in the Rashbam out of place? (I found one current author, the "Seder Pesach ha'Aruch," who noted this as well but does not suggest any answers.) I have not yet found any source for the order that the Rashbam writes. The order of Rashi, as you wrote, is the order in the Torah, and this is also the order written in the Yerushalmi here, and in the Midrash (Bereishis Rabah 88 and Shemos Rabah, beginning of Parshas Va'era).
However, an interesting suggestion may be made in light of the the Rashbam in Bava Basra (58b, DH Revi'is). There, the original Girsa in the Rashbam's words is "v'Hotzeisi, v'Ga'alti, v'Lakachti, v'Hevesi ." That is, he leaves out "v'Hitzalti" entirely -- just as he leaves that word out of its proper place here -- and instead counts "v'Hevesi," as the fourth word (which also appears in the Torah as the fourth of the Leshonos of Ge'ulah, but which is not included in the list in the Midrash).
It seems that the Rashbam had a Girsa in the Midrash that did not include "v'Hitzalti" but did include "v'Hevesi." Apparently, this is what the Rashbam originally wrote here in Pesachim, and the printer changed "v'Hevesi" to "v'Hitzalti" because he knew the Midrash does not mention "v'Hevesi!" That is why v'Hitzalti is listed last in the Rashbam. However, if we change "v'Hitzalti" here back to "v'Hevesi," in accordance with the Rashbam's Girsa of the Midrash, his order is correct, placing "v'Hevesi" last.
Thank you for bringing up that interesting point!
-Mordecai