First : The council in Trullo hasn't been accepted by all Christianity, it wasn't even supposed to teach anything reguarding theology but was meant as clarification for the 6th council.
Second, the year 6109th could literally mean anything, it doesn't have to mean year 6109 since the beginning of times.
We are in the year 2024 Anno Domini, doesn't mean the earth is 2024 years old.
This could very well be an account of years since adam and eve, because we know their ages as described in genesis, but before them there's a whole creation that's not being taken into account.
Also, just a number in a line addressing the marriages of priests is a very weak evidence for the rejection of very complex understanding of the world. You are ready to reject a theory about the world that was found by a christian priest ("Big Bang" was a mocking term used by atheists to mock the idea of a beginning to the universe), based on a number that you interpret as meaning the beginning of the world ?