Yes I would say all are male. Combs being that big and that red so early in development is not a good sign regardless of whether they're a large-combed breed or not. As an example here is my brown leghorn/cream legbar mix at 4 months:
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And here she is at nearly a year old:
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She has one of the largest combs in the whole flock, but it didn't get big until she was much older. Females' combs shouldn't turn red until around point of lay, and usually they don't grow very much in size before then. Early comb development, especially with reddening, should always be looked at suspiciously because chances are it's a rooster.