LM5088: Regulation lost after change in load

In the original system design (the attached pdf 12V out) Web bench LM5088 regulator design supplied 3 gate drivers, a 3.3V LDO and a off board 5.0V LDO.  Both the 3.3V LDO and LM5088 ran very hot but did maintain regulation until the 3.3V LDO overheated and failed.  I have change the LDO to a 3.3V switcher however, the LM5088 now fails to achieve regulation. The best it can do is 8.2V  It seems to me that this is a load issue. I've to artificially load the device with a 1K resistor but that didn't end well.  The part tried to regulate but failed. Any thoughts on a solution would be greatly appreciated. Webbench design.pdf