So you plan to get finace visa then both fly back to the uk then two months later fly back to the phill to get married sounds logical enough but i would check if possible. Like eula says it may confuse passport control if your married when you enter on a finace visa. also maybe problems with proving your married as the NSO certificate takes a while to come though.
I would do some serious checking that this will not cause a problem somewhere along the line.
Personally I would go along the get married in phill and apply for spouse visa. It may take longer but less likely to cause possible problems.
That or get finacee visa have registry wedding here then sort paperwork for flr. Then go back to phill for a blessing so your now wifes family can celebrate in style.