I interpreted your words in two ways - the literal and metaphorical:
In the metaphorical, I explained that you can't literally make the comparison between a person and their shadow when the metaphor just means the difference is really big.
The difference between a drop of water and an ocean being a common example of a similar metaphor. It just means that there is a large discrepancy in power, but not a literally numerical difference between a drop of water and the ocean - the same can be said for The Dog and its shadow. You can't take the comparison literally, its a metaphor.
In the literal, I told you that the comparison is meaningless because a shadow, or whatever equivalent of a shadow that this being has, isn't what is causing the destruction of the timeline - because that's not how shadows work unless they were magical or something, which you explicitly said it wasn't. Shadows don't cause anything, they are the lack of light, they are the lack of a cause.
I literally broke down the two ways you told us to think about this, and you say I am making assumptions and am misconstrued on the nature of The Dog's shadow. How am I reading my interpretation when I am going off of what you said?
Also, what are you talking about, shadows and darkness are the total or partial absence of light.
They aren't 2-D objects cast upon by higher beings. Shadows aren't an object or a thing, they are the lack of a thing or object - light.