That fits very well with my understanding of their migration. I'm also reading this write-up which specifically refers to the brothers, William and James, who became, respectively, first Protestant minister and Constable of Killybegs, and they were settled with established clusters of houses by 1609.
It's very likely then that two of those eleven Hamiltons are William and James, and that they were at least Undertakers. The Strong website says they leased land for Killybegs from John Murray, who was possibly the Chief Undertaker, going by the rules of settling (and it makes sense that one brother was a Constable, capable of dealing with Irish insurrection).
The search Muster Rolls only shows a John Hamilton of Rapho/Raphoe, but the dates are a generation later.
Happy to join the Ulster Scots project! I hope I can contribute. :)