Being omnipotent is not at all the same thing as stopping for a moment and deciding it might be a good idea to have someone on equal footing with a black sister check out the house before attacking. She could have easily let one of those "expendable" sisters try to find out information about the house Hark found before forming an inadequate invasion force. One of your points, about even awesome men not being up to such a task, means that it was very unlikely that Hark had seen all there was to see other than what they wanted him to see- therefore proving that rushing in there on his information alone was ridiculous. Not to mention trusting that a black ajah sister wasn't lying when she said there were only two of them. Hello.

And to be honest, when Elayne herself makes more than a few comments about her own "omni-potency," it's not all that odd that readers will treat her as though she acted that way. She not only claims that she will be fine because of Min's viewing, she also doesn't accept critiques of her plan from people who may very easily not be fine.