electrical short 1 channel. Cable spade at fault?

Excuse my electrical ignorance,but my YBA 201 is now out 1 channel after new cables.The spade connector to the amp was huge in diameter, 3/8ths inch vs 1/4 in.for the post,and even with it fully tightened there was still some motion possible in the cable-post interface.Also ,the spades were so long that there could have been some contact between the two.
Also,any ideas on what it should cost to fix this?
Thank you