> I suggest that we "loan" 2 of our current 4 people to the back-end
That was your biggest mistake.
In abstract theory, moving developers from frontend to backend might have sense, but in practice you moved developers from capable tech leader (you) to incapable tech leader (K).
So, in essence, your suggestion made these two developers to wasting their time and, ultimately, quitting in frustration.
At the time of your "loan 2 developers" suggestion did you know that K was a clueless developer/lead?
That was your biggest mistake.
In abstract theory, moving developers from frontend to backend might have sense, but in practice you moved developers from capable tech leader (you) to incapable tech leader (K).
So, in essence, your suggestion made these two developers to wasting their time and, ultimately, quitting in frustration.
At the time of your "loan 2 developers" suggestion did you know that K was a clueless developer/lead?