A back formation from mksnw or the like! The afel of this verb is the regular rendering of Hebrew piel of יסר in Targum Psalms, while the mss. of Targum Job are quite uncertain between the D and C forms.
The lone CPA example is almost surely to be emended (or re-read?) as a form of kwn Dt, i.e., read "ܘܘ" instead of "ܣ".