The individual state parties set the former, including any rules on "bound" delegate. The RNC establishes more general.rules governing the ci vention itself.
The RNC is the wrong entity to blame if you don't like the delegate selection rules within each state.
Perhaps more germane to your low-information, you must have missed this news item which refers to the FIRST BALLOT votes/delegates, which Cruz is going after:
In case you missed this widely reported story:
A Republican National Committee Standing Rules Committee member told the membership Friday that convention delegates are not bound to cast their votes at the convention according to primary vote results in the first round of voting.
Curly Haugland of North Dakota, a long time member of the RNC Standing Rules Committee, sent a letter to the RNC membership at large about this issue. He explained how he came to the conclusion that all Republican delegates who participate in the 2016 Republican National Convention are unbound on each ballot round, including the first.
Lining up previously Trump-committed FIRST BALLOT delegates is what Cruz is doing.
Please get fully informed via readily available information on the Internet before wasting the moment it takes for the reader to realize you are a Cruzer and therefore will say ANYTHING and pull anything out of your a$$ if it helps your Cruz argument, despite that you've never researched it or any other relevant information about this campaign and its candidates for 3 seconds. Take a week off and READ READ READ on the Internet. That would be my very honest suggestion to you and all the no-info Cruzers on so many subjects, not the least of which is the issue of "natural born citizen."
FINALLY----if you refuse to inform yourself, let's compromise, and you promise to research and understand EXACTLY now Cruz sneaked in TPA and TPP, which Cruz did using cloture rules and various other parlimentary procedcures to remove from Congressional approval or change TPP, which Ted and Heidi, Goldman Sachs, Robert Zoellnick (father of NAFTA), crony capitalists everywhere, the Cheap Labor Express and open borders supporters everywhere...
And it lays the foundation for the North American Union, fully developed and planned by Heidi Cruz while she and Ted were working for years in high positions at the Bush White House. The plan was, and maybe is, that Cruz will be the Supreme Leader of the North American Union, since he isn't legally elligible to be either US Senator or US President. All NAU borders will be obliterated, and all WORKERS from signatory countries can enter the USA and take jobs. AND Cruz stealthily got TPA passed so that CHINA can come in and congress can't stop them.
We have about 150 million jobs in the USA. Chinese and Indians will get ALL of these jobs under TPA. Those countries additionally face no tariffs or taxes on ANYTHING they wish to sell here, but US Exports we wish to sell there are either banned outright, or have applied to them a prohibitive tax/tariff making them prohibited de facto.