I'm listening to the audio novel right not in the epilogue. Loghain is not even in the same city when Maric meets Alistair.
The problem with this is on the metalevel.
In the game- the primary story, the one most of your consumerbase is going to experience, the one the bulk of your budget is going into, you present one set of circumstances.
In a shoddy, hastily written prequel novel that you don't have the time or budget to give a proper editing cycle towards, you present a completely incompatible set of circumstances.
You then choose the latter as your official canon.
Loghain now looks like either a madman or an idiot ranting about things he has no knowledge of as if he has first hand knowledge of them. I suppose this isn't much of a problem if you hate Loghain as a good bit of the fandom do, but for his fans, this is an issue.
On top of that, Alistair's whole personal quest; his finding of his "mother's" locket, his meeting of his sister and finding closure there, all of that becomes completely meaningless.
And what's the gain? Alistair's mother is a poorly written character who he has a good chance of never meeting? How does this enhance the story?