Welcome to RV.net. And you're from Santa Cruz! CA? The beautiful Santa Cruz with the Amusement Park and the Crows Nest Restaurant? Love that place!
I mounted our first flat panel, a 26", to the forward inboard corner of the driver side cabinets. Used a folding wall mount from Amazon, about $20, Video Secu brand. Didn't trust screws so I through bolted it. Attached a small bungee cord to the cabover window frame and it holds the TV from swinging around underway. Just replaced 26" with 32" and found it still clears the cabinet to get into viewing position.
How were you mounting your TV that it's cracking? There's a VESA pattern of four threaded inserts on the back, for metric mounting screws. Did you use that or something else?