I love "what if" type stories and exercises, regardless of any practicality. I assume that, as part of the win, each group has eradicated/absorbed the other groups. So, let's see…
The Foundation -
Final, total control of all items. Everything with no direct research value, overly dangerous SCP, or things non-vital to reality are decommissioned. The remaining items are held, studied, and utilized for the betterment of The Foundation and, by extension, humanity. Life continues, with additional oversight by The Foundation, posing as various groups. The chilling bit is that normalcy is maintained. Forever. Advancement is carefully parceled out, no sudden leaps or upheavals. No wars, riots or other social unrest outside of a very strict, well-maintained schedule. Everything is regulated to keep humanity happy, safe and alive. Think the matrix, but with everyone awake.
The GOC -
Any and all items of anomalous nature are decommissioned, unless they carry a easy to control ability that can be duplicated consistently and will not get out of control. After what would probably be a rather messy, prolonged battle, the GOC would step back a bit. Slipping back under the radar, they'd become something like the CIA, but worldwide. Another "secret" group, working with, but outside, world governments. Maybe some fiddling in things here and there, but they are more a watchdog.
The Serpent's Hand -
The gates are more or less slung wide. Dangerous items are suppressed, relocated, or even in extreme cases, destroyed. Humanoid SCP items are cared for, instructed and supported, eventually "coming out" to the world at large, along with a great deal of various items and effects. From there…it's hard to say. Probably wars, here and there, as some groups and nations resist the changes, and others welcome it. Eventually, i can see the world settling in to a mash of fantasy, cyberpunk, steampunk, and various other fictional elements, along with vast amounts of people just trying to make their way. From there…well…skies the limit.
The Church of The Broken God -
Clockwork apocalypse. Sorry, just always wanted to write that. Anyway, various SCP items are joined and spread, causing a accelerated nightmare of mechanical suppression and conversion. I think the transition time would be the most interesting…massive, spreading patches of metal and horror, swallowing up the land inch by inch, wars being fought against a relentless, tireless foe. Inside the spreading clockworks…nightmares. Imagine things like 015 and 455 integrating with the clockwork ecosystem, spreading and…evolving. Eventually, most of the world would be absorbed, and the resulting…Awareness would turn its gaze outward…other worlds, other "Gods", who's to say. Imagine, being hold up in some of the last normal patches of earth…ruined cities, caves…hearing that endless grinding…
The Chaos Insurgency -
I can barely imagine…somewhere between the Nazi Party/1984/Warhammer40K.