Use some triage with

At first I felt the word had been misused, but looking at the etymology:

1727, "action of assorting according to quality," from French triage "a picking out, sorting" (14c.), from Old French trier "to pick, cull" (see try (v.)). There seems to be some influence from or convergence with Latin tria "three" (as in triage for "coffee beans of the third or lowest quality"). In World War I, adopted for the sorting of wounded soldiers into groups according to the severity of their injuries, from French use.

So the guy presumably "culled" the unlikely candidates, then picked one that seemed pretty good for his "back door".

Some confusion arises from the use of "triage" in medicine where patients are divided into three categories in an emergency situation: Those who are too seriously ill/injured to be worth treating (and hence will be put off til last), those who can benefit from immediate attention, and those who can wait to be treated.