Let \( x=2 \) be a local minima of the function \( f(x)=2x^{4}-18x^{2}+8x+12,\, x\in(-4,4) \). If \( M \) is local maximum value of the function \( f \) in \( (-4,4) \), then \( M= \)
\( 12\sqrt{6}-\dfrac{31}{2} \)
\( 18\sqrt{6}-\dfrac{31}{2} \)
\( 18\sqrt{6}-\dfrac{33}{2} \)
\( 12\sqrt{6}-\dfrac{33}{2} \)