That's pretty much the sentiment here. The problem is, we don't know how.
Well I did suggest easing her into it by getting her involved in de-Contracting research and thus nudge her into stumbling upon the concept of Karmic Potential on her own (and hopefully a way a manipulate karma as part of that research, which would give her some hope of reversing the karmic buildup) but besides us not having reached an appropriate point in time to bring up the notion, I'm not sure how popular it was with everyone else.
The particular variant I thought up involved bringing in Kanna Niko to head up the research and there seemed to be bunch of resistance around that idea.
The way that usually goes is that Firn plays into the "thread is Sabrina's thought processes" thing and has her realize that she could/should have done something else partway into the update, often when its too late to adjust things.
It's very rarely an issue - usually the vote gets settled with days to spare.
Speaking of this, I'm going to play devil's advocate since this particular vote looks like it's going to end up either 1 of 2 ways, which is either telling Kyoko about Mami's loneliness or telling Mami about Kyoko's reasons behind the split.
I really feel like both are equally unfavorable. Mami's deep-seated loneliness isn't really our story to tell, even if her insecurity might be evident to those close to her. She does keep up her sempai facade for a reason and the last time we tried telling Kyoko that Mami missed her, Kyoko didn't believe it. Trying to do so again might, indeed, just lead to a rehash of that last conversation as another poster pointed out.
Meanwhile, Kyoko's losing the use of her Rosso Fantasma and her reasons for splitting with Mami are even less our secrets to tell. Sabrina might be close enough to Mami that Mami might trust us sharing her insecurities, but we're not in any way as close to Kyoko - and declaring that we are going to tell Mami about it anyway is the sort of ultimatum that, if it doesn't result in her trying to spear us on the spot, would probably back her into a corner and make her very uncomfortable.
Yes, it might pressure her into meeting with Mami if only to avoid us heading her off so that she can explain first on her own, but it's not nice and wouldn't score us many friendship points (might even score us negative points).
The way this vote is going, it looks like one of those two is going to win out. So I just want to throw those misgivings out there now so that if it does go up in flames, at least Sabrina can honestly say later that she had doubts over it when she throws Sayaka in front of Kyoko to extinguish the fire.
A promise to be close by enough to bail her out, maybe having cake in a highly public eating location where Mami wouldn't want to start a fight - any of these, I feel, would be enough to assuage her misgivings, even if she doesn't believe us about Mami not being out for her head.