First, you mean one of his staff. Mad scientists have underlings.

Second, you have literally no idea how much input he had into it. He may have come up with the name himself, or he may have directed his staff to come up with something pithy that spells out "Bezos" or he may have sat around with them spitballing ideas until they came up with something good. But in the end, he was the senator who introduced it, and he gets the credit.