Are these two men the same person?
Family search M86P-3Y8 and L8T6-FP6
Could you provide the full url's of the Familysearch records you found for thes persons? with what you provided these records cannot be located...
I think Dingenis Lavo(o)ij who (widower) married Maatje Brouwer and had children Jacob Marinis and Elizabeth with her is the same person as this Dennis Lafoy: "New York State Census, 1855," database with images, FamilySearch(https://familysearch.org/ark:/61903/1:1:K6SY-8SG : 13 March 2018), Dennis Lafoy, E.D. 1, Avon, Livingston, New York, United States; citing p. , line #31, family #71, county clerk offices, New York; FHL microfilm 510,541.
This Dingenis indeed has the two profiles on Familysearch referred to in the question.
Both have 22 Aug 1802 as DoB, but that actually was the date of baptism. He was born 19 Aug 1802:
"Netherlands, Zeeland Province, Church Records, 1527-1907," images, FamilySearch (https://familysearch.org/ark:/61903/3:1:3QS7-99QJ-S84M?cc=2036997&wc=MCLG-627%3A345031601%2C345105001%2C345129001 : 22 May 2014), Nederlands Hervormd > 's-Gravenpolder > Dopen 1753-1810 Overlijden 1806-1811 > image 53 of 103; Nederlands Rijksarchiefdienst, Den Haag (Netherlands National Archives, The Hague).
Also, https://www.familysearch.org/tree/person/details/L8T6-FP6 has marriage data as 1835 to Maria Brouwer. Should be 12 Dec 1833 to Maatje Brouwer.