Nothing really concrete, but can you not take a screenshot of the address if it's still logged there on coins.ph? That may satisfy some but not others but someone will likely buy your account without a signed message but it'll fetch less and I wouldn't recommend it.
I see , but the address wasn't logged in there anymore, it was replaced with a new one
Have you ever posted your twitter or fb account name for some giveaways or probably social media campaigns in the past ?, if yes and you are still have control with those accounts maybe it will help you to verify that you are real owner.
Can't remember, i think i only posted my email(i used to register here on bitcointalk) here