No one can tell you definitely what will happen. With them raised together it should improve your odds of a good ending, but no guarantees.
The ratios given are to assure that the eggs are fertile. In normal circumstances, one full sized fowl rooster can keep 10 to 12 hens fertile. A bantam can probably handle 12 to 15. But a lot depends on the individual rooster and his age.
The other issue with the rooster-hen ratio is that if you have too few hens per rooster, sometimes the rooster can injure the hens when mating. This is a little harder to give a good answer because it very much depends on the individual rooster. Some people have 1 rooster and 2 hens and have no problems. Some have a ratio of 1 to 10, the rooster has a rough technique and long spurs, he picks favorite hens to overmate with, and he injures them.
With two roosters in the same flock, what will normally happen is that the two roosters will decide which will be dominant. This process can be pretty violent, but as long as no blood is shed, you should not interfere. They will decide, so don't draw out the process and make it harder on them. If one starts bleeding, that is a different situation and you should interfere. Once they decide which one is number 1, they form a very good team in taking care of the flock. The dominant rooster gets his pick of the hens, but the other gets his share. It does help if they have some room to separate but this is not absolutely necessary.
Sometimes the two roosters are so closely matched in spirit that neither will accept the number 2 position. In this case, one will kill the other. And sometimes, one rooster is so much stronger than the other that he will kill the weaker, as if to say, "I don't want your dna around my flock". These are the two situations you need to be on the lookout for.
I think you are taking the correct approach by waiting it out. With them being raised together the odds are pretty good in your favor, but they are living creatures and anything can happen.
Good luck!
