One of the reasons he lasted until #27 is that he was a project. H
Had he been clearly NBA material, a player of his size would have been top-5 or 10. Im no Corbin fan, but Rudy was not ready for a major role. You look at mins played and he was still getting reasonable burn as a rookie backup.
Its not unexpected for any later draft pick to get some stints in the DLeague where he can get more playing time, more shots, etc. I think Rudy had a pretty good development curve. Its not like Lindsey had him spend essentially the entire year in the DLeague like Bradley. Nor was Rudy the equivalent of a Kuzma or Mitchell who were 100% ready to be starters.