So you have kicked the can a little further down the road. Congratulations!
You haven’t, however, actually succeeded in answering the question of how – if existence is blind, unguided and materialistic in nature – morality could possibly be sourced in existence itself.
Your problem, it seems to me, is that as soon as you begin sourcing morality in existence you have to be imputing existence with God-like qualities, albeit with the essentially meaningless proviso that existence itself just shouldn’t be referred to as “God,” even though it remarkably shoulders all of God’s classic traits.
You still haven’t shown how morality can be derived from an “existence itself” which is fundamentally causal, unguided and material with no intentionality, no foresight nor any concern for those particular things which are instantiated as individual existents.
As soon as you begin endowing “existence itself” with intentionality, foresight, concern, purpose and interest in those things which do exists – and thereby make existence itself morally available to an atheist, it is at that point that you begin bringing God into your narrative, but merely deny that you are endorsing the use of the word “God.” Sounds like a distinction without a difference or you suffering from the problem of “having no reliable means of distinguishing between” God and existence itself (in a form which is morally available to an atheist.)
Well, okay, but your objections to theism have simply evaporated like so much morning dew.