Milbourne served as a steward at the Jesuit college at The Cwm which was owned by the Worcester Estate, in the parish of Llanrothal, Herefordshire in the 1670s.
The Jesuits' South Wales Mission was originally based about 14 miles to the south, in Raglan, Monmouthshire, but soon after the year 1600, their Superior received from the Earl of Worcester an estate called The Cwm in the parish of Llanrothal.