I think that from a PR standpoint, they should welcome them with open arms in their capacity as Congresswomen and say that from the rhetoric they espouse, they clearly don't have an accurate picture of Israel. They should give them grand tours and princely treatment. Then, after they return and keep talking against Israel, they will be fair game, and they won't have the excuse that they were't let in. Israel can say that were glad to show them the truth but they obstinately refused to see.
It would make more sense from the public perception standpoint.