Umm... Ignoring all the one-line posts above me. 'Cept Nath. Good work.
Could it happen? Yes. Anything can happen, unfortunately.
Should it happen? Honestly, I think not.
Really, I strongly dislike the series. Mostly because all the previews on SciFi are ill-lit and the camera man appears to be having a seizure while having his hand on the zoom buttons, but also because along with the rediculous camera work, somehow attempting to create drama by zooming in and out on peoples' faces, its just drowned in drama. All the actors appear to suffer from a morbid depression and a failure and apparent inability to properly convey emotions without making it seem like Days of our Lives. Right... Sorry about that tirade.
Really though, the Cylons are only in Disco's history because the BSG underwent a myriad of reforms under the pressure of constant griping by the community and thus - existed. Beyond that, they really shouldn't have ever existed here and they really don't fit. If you consider that FL is a story of the future... Hmm... Inability to express points. Lets try this.
Earth exists. However much time passes, Coalition and Alliance start fighting. Coalition wins, Sleepers launch, Sol gets torched. Now, presumably they've kept records. And games like this are meant to tell a story of the future, implying that it is our day and age, plus however many years. Therefor, Battlestar Galactica as a show existed. So if Cylons, these fanciful creatures of myth kept alive by millenia old "motion pictures", suddenly swarmed into Sirius saying they were rogue Cylons, they'd probably be detained and put into a mental institution.
If you think that you can mix fictions, then... I guess thats just your opinion as to how FL developed over time. If you think its a different Earth under different circumstances, with a different past preceeding the Alliance and Coalition, then go for it. But its my opinion that it was our Earth a few hundred (maybe a thousand for all we know) years in the future and that it would make about as much sense as Eragon flying onto Manhattan with a dragon or legions of orcs being dropped onto the city streets to kill the people as per request of Sauron.