This defies common sense. Too many people for what amounts to an easy operation.
In most circumstances, assassination is easy, because the assassin chooses the target, the location, the time, the method, the routes to and from, and any obfuscation or deception. This is a huge advantage, and only bombers have it easier.
It is alleged that four individuals went into his hotel room, where he was staying alone, and that they suffocated him. Terrible technique, if anything. Shows lack of professionalism.
In the 1980s Israel dressed up dozens of commandos to kill a PLO bigwig in Tunis. The men were dressed up as women, landed from boats, and one “woman” videotaped the entire operation. It is believed this was done to show that even Israeli women are tougher than the cowards of the PLO who hid in mansions in Tunisia.
I know this is not the same situation, I am just saying maybe there is more to it, such as providing multiple levels of assassins in case something does not go right. Or providing logistics to get out of Dubai.