The lifecycle of uronema is not as well understood as many other diseases, but we do know that it is a free living parasite which does not require a fish host to survive. It can consume detritus for sustenance.
What I would do in your shoes is wait 6 months, QT 1 Starcki Damsel, and then introduce it into your DT just to see what happens. Perhaps the parasite is unable to reproduce after a period of time - this is true for ich. With ich, a given strain will die out after 100 generations or so. Given the average life cycle of ich is 2 weeks, this could take almost 4 years (on average).