I'll try. However, the reasons that you cite as evidence of strong ties to the Philippines are not ones that will have changed between the visa applications, making itless likely that an officer in Vancouver is going to issue over a recent denial in Manila, anecdotal evidence to the contrary. Nobody kows all of the issues in specific visa cases, making it impossible to accurately compare two or more cases. My opinion.
While the issues you cite as strong ties are not specifically country specific, they are influenced by local cultural norms. For eample, you think the presence of a young son is an automatic reason to ensure someone returns home, based on your family/cutural norms. That is not a "given" in many countries, including the Philippines. Many parents leave their children in a home country to work in another, legally or otherwise, believing they are providing a better life for them. You mention that your fiance previously returned home after working internationally. Likely her son was not with her then, so it shows that she is willing to try to provide for him even if it means she must leave him. You also said she is "currently" living with him and caring for him, indicating that she has not always been able to do that. (Not judging--just trying to help you see entire picture from a visa perspective). Her visa application would have shown her work pattern inside and outside the Philippines, whether the officer asked about it or not. Information on these types of issues are best adjudicated in the home country or country of residence than a third country after a denial in the home country.
`You mentioned the quick denial after only a couple of questions; however, in addition to the information on the application form, those two questions actually provided a great deal of information. For example, the information that you are her sole financial support showed that she has no/limited financial reasons to return to the Philippines -- no job, etc. It is likely cheaper for you to support her with you in the US, even if it means still sending some money back to support her son. You not at least being in the processing of acquiring US citizenship (regardless of the reason) means that the legal means for your fiance to immigrate to the US will take a couple of years -- much longer than it would be for a spouse of a US citizen -- so some couples are more wlling to try to find means to make the wait apart shorter, whether those means are legal or not (again -- not saying this is what you are planning -- just showing you a different view).
Hope this helps at least a little.....even though it isn't what you want to hear. The decision, of course, is yours/hers.
