Wiktionary
fink out
vb. (context idiomatic English) To avoid or shirk, either by failing to perform, or by performing in a grossly insufficient, negligent, or superficial manner.
Usage examples of "fink out".
Something about the Outfit, and something about her husband thinking she was going to fink out, and something about pushers.
The tones sounded five times, and I was just beginning to think that Harry was going to fink out on me in my hour of need when the screen rolled once and came back up with his homely, balding head looking out at me.