Either way, "first cause" is something, otherwise it is nothing. If it is nothing, then the logic "something can't come from nothing," means that the universe couldn't have come from the "first cause." If it is something, then the logic "something can't come from nothing," means that the "first cause" couldn't have come from nothing, so must have come from something else.
If one of you has some sort of logical argument which refutes this, I'm more than happy to hear it.
Would it help? I'll try. What you refer to as "the logic" that something can't come from nothing is an axiom (a statement accepted as true self-evidently). It is substantiated definitionally, holding nothing (no thing) to be the lack of something (or everything).
The words we choose to describe things have power.
"First cause", if there is one, is necessarily beyond, and imagined as the foundation (cause) of, both something and nothing. Both "something" and "nothing" are constructs of language representing ideas about the world. When we take away both something and nothing we are left with a void. That void cannot be said to exist or not exist, to have form or formlessness, to be full or lacking (empty), to be source or sourced, to be near or far, large or small, logical or illogical, etc. All of these things are somethings, for us, that together compose the world; that void is "supra" to the world. It is the image of a cause of existence --all around us, here and now.
We are left with only words to describe it.
"God" has an "ineffable" name because
no words can describe "God". This is reflected in scriptures about the G-D of the Jews (including Abraham), the Allah of Islam, the Brahman of the Hindus, etc., i.e. the "primeval essence, or
unconditioned, self-existent substance".
"All things in this creation exist within you, and all things in you exist in creation; there is no border between you and the closest things, and there is no distance between you and the farthest things, and all things, from the lowest to the loftiest, from the smallest to the greatest, are within you as equal things. In one atom are found all the elements of the earth; in one motion of the mind are found the motions of all the laws of existence; in one drop of water are found the secrets of all the endless oceans; in one aspect of you are found all the aspects of existence." (Khalil Gibran)