No, only "a" is natural. There is no real platter - it just means that it wants all the hard parts done for him with no work on his part. If you say he wanted someone "served up on a platter," that's a reference to the beheading of John the Baptist, and it means he wants that person eliminated -- not really murdered, just fired or removed from the project, or possibly brought before him, where he will be in a great deal of trouble.
New words, one handy idiom, and a 2-minute quiz — delivered to your inbox to keep your streak alive.