It appears that Microsoft had to pull in some extra help recently in order to get Halo Infinite in running shape ahead of its upcoming release. This help may have even come before 343 Industries announced a delay that has set the launch window as far back as Fall of 2021, as opposed to arriving sooner within the Xbox Series X's first year.
New reports suggest that some of the workload for Halo Infinite, specifically in areas of art and level design, had been shifted over to a fellow Microsoft Studio during development. While this isn't an uncommon practice for publisher's to pool resources from multiple development studios at once, this could possibly explain why Microsoft and 343 Industries remain so confident even after delays.
Several updates to the resumes of artists who either currently or formerly worked with Gears of War developer The Coalition have added work on Halo Infinite under their duties while employed by the company. Much of the specifics of the work these artists performed is not included in the public resume, though the job titles do suggest that the developer was brought in to finalize level design. Considering the reported size of Halo Infinite's campaign, it's likely that there were dozens of maps that needed the extra attention, especially after criticisms of recent trailers began to appear online.
As far as finalizing Halo Infinite's art and level designs goes, it's likely that much of this work that got offloaded to The Coalition could have been the more minute details of the game world. The process itself is often more complicated than simply placing a few trees and plants to fill up space, and often comes with a number of checks and balances to make sure that nothing game breaking or exploitable gets added. In that case, the Gears of War developer was likely a strong pick, not only because Microsoft could pull from the Xbox Game Studios, but because its previous titles have often had full, bustling environments as well.
Looking at the initial backlash that spawned Halo Infinite's Craig meme, and then the resulting response from fans as 343 Industries announced that the game would be delayed, this is probably the best choice for the developer. Even if it is relatively smaller aspects of the game that are going to The Coalition or any other studio that might get brought in to get the title shipped, this could be a strong step towards meeting the next deadline. Hopefully this means that players can finally get their hands on the next Halo title sooner rather than later.
Halo Infinite is currently in development for PC, Xbox One, and Xbox Series X.