Yeh, that was my tentative understanding as well, hence my statement above:
Can we assume that God bestows or allows souls to certain creatures? I will assume so.
I agree that the OP seems to be making an implicit assumption to the contrary, which is why I’m trying to put out alternative explicit assumptions to see where the point of conflict is.
Addendum:
It further occurred to me that the assumption that souls are bestowed “at conception” would mean that many souls are attached to zygotes that never develop further as they don’t attach to the uterus. Whilst this isn’t a strong argument in favor of souls for non-human creatures, it does make the argument against them just that little bit more tenuous.
As I said, make explicit assumptions, and see where that leads us.
Further addendum:
I was talking about “serious discussion”. I’m quite happy to have interesting discussions on such nebulous topics, but don’t expect to take them seriously.

On the other hand, just because we don’t know the precise nature of consciousness doesn’t seem to prevent us from using it and recognizing it in some incomplete way.
The problem I have with some philosophical discussion of consciousness is that it can be so woolly that it is difficult to tell what is being discussed. This is particularly true when panpsychism is on the table, as this broadens the definition of consciousness sufficiently far that I find it difficult to view as intelligible. It’s rather like trying to have a discussion/debate over whether ducks are nice birds, only to find that the definition of ‘duck’ has been widened to include seagulls, buzzards and maybe turtles. We have a hard enough time trying to get our mind around what consciousness means for people, trying to work out what it might mean for rocks is just a mess.

We often use things we don’t fully understand and sort of learn by using. I tend to think Christians gain a better understanding of things like the soul as they experience life and interact with other souls. Doesn’t mean we understand it all that well, or can articulate a definition, or provide the empirical evidence I’d love to have.
Yes, and that lies reasonably close to what my problem is with quite a bit of philosophy. It elevates the subjective over the intersubjective. You can try to tell me what it feels like to you to have these experiences that you associate with what you think of as your soul. But you therefore cannot tell me what it is like to live without a soul, so you cannot give me any information that is relevant to the question of what does a soul actually do? Likewise, it is likely that people of other religious traditions have numinous experiences that they interpret through the framework of their traditions, possibly in manner that is unrecognisable to the Christian tradition.
None of this argues that a soul may not be important, just that discussion of it may be too deeply rooted in subjective experience to be productive.