I feel I need to point out, I don't know if my Ambroise is illegitimate (there are other possibilities), & I'm skeptical if that 1816 baptism is my Ambroise, as that would actually make him younger than he said he was, which isn't something I've come across too often (with 1 exception, he is consistently shown as being born abt. 1813).
The only thing I know about his origin is he lived in the parishes of St-Antoine-de-Tilly & St-Augustin prior to his 1850 marriage in Baie-du-Febvre. I haven't found any records for Verboncoeurs, Vadeboncoeurs, etc., in those church records, but was wondering if someone had some knowledge of any being there. Perhaps even under a dit name (I haven't seen the family use anything other than a spelling variation, but it is one possibility). This would seem the only legitimate lead I have to follow, unfortunately everything else seems to be speculation,