I rechecked the microfilm for St. Helen's, Chasm Falls, this afternoon: the marriage record reads: 1887 margin: M.3 [G]ilbert Gilbort & [Ce]sarie Boyer (page worn on edges) text: "Le onze Avril mil huit quatre vingt-sept. Nous pretre sousigne avons recu le mutuel consen- (page break) tement de mariage entre Gilbert Gilbort fils majeur de Francois Gil- bort et de Virginie Villeneuve, et Cesarie Boyer, fille mineure de Joseph Boyer et de Lina Paquin de cette paroisse. Temoins, Albert Gilbort et Celina Boyer. D.J. Halde, ptre"
I also found the following in "Marriages of Franklin County, New York: Vital Records Copied from Original Malone Palladium Newspapers by Elizabeth (Smith) Slattery. Vol. 2 (1986). Compiled, typed, additions made & indexed by Virginia Anne (Croissant) Wolfe." Apparently a D.A.R. Records Committee project:
page 15Malone Palladium Marriages
"Gilbert, Bert (sic) of Bangor, married at St. Helen's Roman Catholic Church in Titusville, on 11 April 1887, by Rev. D.J. Halde to Miss Sarah Boyea, daughter of Joseph Boyea of Ringville. (St. Helen's Church is in Chasm Falls, NY)."
Their are also some extracts from Malone obituaries, though I didn't find any Gilberts killed by wagons.
As far as the name of the groom's mother, I can certainly see Jane coming from "Vir-ginie," in a society where Clement becomes Amos and Cyprien becomes Levi on a regular basis. As for the surnames, between the "dit" names, the anglicaztions, and errors in the records, who knows!