Why does "Nice, i will take your father on" not work?
Maybe it's too idiomatic? "To take on" could mean "to hire" but it's really sounding more like slang to me. I tried a similar translation and then reported the hints were inaccurate.
It should; “take on” is a common way to express this. Please report it.
Of the 14 definitions offered for "einstellen", "hire" is not one of them. I used "call off" and it was marked wrong. Would "I will call off your dad" be an impossible interpretation?
Yes, that would be an impossible interpretation.
Does "einstellen" ever mean "call off" (in other contexts)?
By the way, you might want to use a proper dictionary with context information.
Yes, it does. Here's an example:
Wir müssen die Suche einstellen. (We have to call off the search)