I think this will work:
- "What's the purpose of your visit?" - "I will be looking for a job in the U.S." - "But you have a visitor's VISA here" - "Oh.. mmm.. but I am coming here to work" - "I am sorry this is not going to work out"
- "What's the purpose of your visit?" - "I will be looking for a job in the U.S." - "But you have a visitor's VISA here" - "Oh.. mmm.. but I am coming here to work" - "I am sorry this is not going to work out"
That should get her entry denied too.
Just telling the truth should suffice. The only issue is if it will cause trouble later on should she try to enter again. I assume it would.
EDIT: There is probably a 'alien will probably overstay' flag somewhere. Not a 'alien will overstay provided she is still married to an out of status alien'.