I personally like Betrayal of Ideals. It shows that the Clans weren't monolithic in the early years but full of internal conflicts. It also showed the insanity of Kerensky at the time and how readily the Clan had its early history rewritten and forgotten. It showed that at one time the Clans main moderating influences were crushed to show Kerenskys willingness to do anything, including wholesale slaughter of a part of his own population to maintain his power and influence.
Regardless of how well it is or isn't written, it still has problems. That the writers cannot build upon it or use it because it IS a secret history that noone knows about is, IMO, quite a big one. That it largely invalidates large sections of Clan history published both before and after it is another. Ohers have pointed out other issues with it - some of which, but not all, can be explained away by the"Victors write the history" storyline.
Reverting to the truth that the published stories are correct, with the Wolverines simply airbrushed out, solves a lot of issues. That also frees up the authors and opens up a lot more creative room for the Wolverines in the (highly unlikely at best) circumstance they return and by stating that the BoI book is a copy of the book published by the Society, then the explanation that it is canon still holds. One could even argue that parts of it are true.
But a book that authors cannot use or reference, which they must even actively ignore when writing in universe stories and explanations, and which contradicts, in letter and spirit, the sources and statements that they can use and reference and build upon is not a source that I think people should rely upon. And, as I have said elsewhere, IMO, doing so also offers up a Clan Wolverine that has so many more opportunities for character and development that would be more benenficial for them as a faction - again, in the unlikely event they did return. Which I do not believe will ever happen, barring a reboot of the storyline.
Let us suggest for example that they were the Minnesota Tribe...what we have would be a small handful of well equipped survivors and troops who picked up tens of thousanbds of Combine citizens. What does this mean? It means that the Clan Wolverine just became a Kuritan offshoot. Now, if the MT were a lost SLDF division, or even a Clan pursuit force, then it woudln't matter. One would likely adopt the Kuritan identity as its own, the other would place the kuritans in amongst the general populace and absorb them.
But for the Wolverines, it means there is probably nothing worthwhile to bring back. The Trial system wasn't fixed or fully formed. Assuming BoI, there were only a handful of them left following Barbados. The Kuritans would provide bodies and possibly skills for labour but with the majority of their supplies lost at Barbados, returning to the type of society they had left behind would be impossible. You could posit a fusion of societies, but it would still be overwhelmingly Kuritan.
If we want a Kuritan society, we can play the Combine.
Which then brings us the the central problem of adding the Wolverines, of bringing them back.
What would they add to the game? What coudl they do that an existing faction could not do at least as well?
The answer is....nothing.
Now - as to the original question, what if the Wolverines were not Annihilated, you need to first ask "Which Wolverines"?
The BoI Wolverines were (in Jellicos words) "The coolest bestest Clan, so awesome even Nicky's overpowered fiat protected Wolves were so threatened and jealous they could not be allowed to exist."
Assume these Wolverines were the true Wolverines, but then posit they escaped Annihilation.
First question - at what point was this managed? Did they defeat the Clan Wolf? Survive the ToA?
Option One: Surviving not being an option (cos then they'd be dead), they win the ToA.Then they'd be weakened, and would become everyones favourite whipping boy. They and the Wolves would be subject to immediate Trials of Possession for most of their enclaves. Nicholas, not wanting to see his society riven apart so soon, would probably have stepped in and imposed some limits on the fighting to ensure both Clans had a chance of long term survival, in effect codifying that Trials could only be waged against a Clan able to Absorb the damage unless it was subject to a Trial of Annihilation or Absorption.
Clan Wolf and Clan Wolverine would still exist, but they would be shadows of their former selves/
Option 2: McEvedy prevents the ToA taking place.
How? Maybe she doesn't nuke Dehra Dun...or prevents its nuking.
Maybe she doesn't point a gun at the Grand Council.
Maybe she accepts that her Clan lost the Trial and doesn't pursue it any further
Nicholas might still find her and her Clan guilty of various crimes and would require forgiveness and penance of some form. Surkai. What form would such penance take? McEvedy and the saKhan would likely be required to step down, with a new leadership installed. Sacrifices of territory, personnel, equipment might be expected. Nicholas might enact a new punishment such as temporary exile - confine the Clan to a harsh planet for a certain amount of time, which would give the Wolverines their own homeworld but stunt their growth.
3: McEvedy doesn't antagonise the other Clans
In all these cases, the Wolverines survive, the Clans still grow, but the Wolverines end up much weaker than they are shown in BoI, but with an opportunity to regrow. Depending on the situation, other Clans would also end up weaker. Without the Wolverines assets, Clan Wolf would not become the powerhouse it did but it would have a larger fleet. A number of feuds which began due to the Annihilation - a factor against BOI - would not have started and interClan relationships might be more cordial. Clan Wolfs Absorption of Clan Widowmaker might not have happened, or it might have gone to a different Clan.