I doubt that completely; the party has had centrist / right wing policies in the past and has stayed united - people who didn’t like it left.
What will kick things off is if the few individuals who remain in post linked to this are found to have done what’s been alleged and yet keep their jobs, it would mean they’ve learned nothing and Starmer isn’t ruthless enough to get rid of people who are no use to anyone (which was Corbyns biggest failing).
Could it not be argued that those that had been in control of the party prior to Momentum's formation in 2015 and subsequent growth, saw Momentum and Corbyn's take over of
their party and either left or stood their ground and ultimately won their party back?
If consider that under Corbyn and Momentum's watch we actually managed to turn lifelong Labour communities into Tory voters - it is quite an achievement! I'm sure there'll be fingers pointing in all directions when considering this but regardless of the variables it is and will remain Corbyn and Momentum's legacy.
I would say there seems to be a general lack of humility coming from those corners of the party and if it is allowed to continue then the party will not move forward as those that can never be wrong are destined to walk in circles and will keep bumping into everyone else.
As I say, it might be best for all if the passionately supported 40,000 odd Momentum members set up another paryt and allowed Labour to get on with the healing the damage. Time will tell whether they can fall into line.