Wrong again. The Rules Committee votes on proposed rules that must be passed by the entire national delegation.
Just to be clear -
There are two rules committees. One is the RNC Rules Committee, the other is the Convention Rules Committee. The RNC Rules Committee will meet in late April, AFAIK. Only the Convention Rules Committee requires a majority vote of convention delegates for changes.
But note that the Convention Rules Committee will adopt or reject or modify the rules put in place by the RNC, and those actions will require a majority convention vote.