My son only had a Philippine birth certificate, it makes no difference, don't sweat about that.
You can get a UK birth certificate at the embassy, but it is expensive, and really it is not more recognised than the Phils one. You can still carry on and process your son's application without needing the uk version. The C2 is the ONLY form you need to fill out for application and supply the docs from the list I posted. Nothing more.
The reforms to the visa application come into force on the 9th July, but if your son is successful in getting his passport, there is no extra earnings needed for him, after all, he is then British and a British passport holder. Other dependant children will need the extra earnings.
hope that helps
