First off, here's an April, 1943 BuAer communique:
This came from around the same time as VF-12 and VF-17 were undergoing carried qualifications (both squadrons completed them by the end of April). VF-17 spent the entirety of the spring and summer of 1943 after completing qualifications embarked aboard Bunker Hill, and were successfully operating from the carrier during that time. It was also VF-17 pilots that helped train the first group of Brits when they arrived in the US in June.
When Bunker Hill was ordered to the Pacific, VF-17 was embarked aboard and fully expecting to go to war from the carrier. It wasn't until they arrived at Pearl Harbor in October that orders changed and they were redirected to Espirtu Santo. Tommy Blackburn was emphatic in his book that it was NOT because the Corsair's were unsuitable for carrier use, but was entirely a logistics decision: The Navy didn't have the supply chains in place to support the Corsairs aboard the carriers, so VF-17 was disembarked to take advantage of the existing Marine logistics.
There's also the strategic situation to consider: The US carrier forces spent most of the first half of 1943 rebuilding. Enterprise and Saratoga were in need of refit and repair, and their air groups were depleted. The first Essexes didn't arrive in the theater until later in the spring, and major carrier operations didn't resume until the fall. The Marines, however, were still in combat and desperately in need of fighters NOW. The Corsair was available in numbers first, so every airframe available (minus VF-12 and 17, with VF-12 eventually relinquishing their Corsairs) was being sent to the Pacific as fast as they could get them off the assembly lines. This meant there were no Corsairs available for the carrier squadrons.