There is a lot more to step 2 than meets the eye, and it can go several different ways.
And sometimes it is possible to get a new coin without a second co-sponsor. (in fact under house rules you need 220 co-sponsors to gat a bill moved to the floor but there are ways around it.) In fact the recenly signed into law Palladium bullion coin had ZERO co-sponsors. It was the result of the the actions of a single lawmaker and it was passed with no co-sponsors, no hearings, no debate, and was never even voted on. It was passed under a method that is becoming more and more common. You wait until the last minute, submit you bill with a request it be put on the unanimous consent calendar. Then if no one objects to it, it is deemed as having passed and it moves on to the other house on their unanimous consent calendar. Since this calendar comes up at the end of the session when everyone is trying to wrap things up and get out of town they don't pay much attention. So we got the palladium coin because on one representative who pushed through a law to benefit a single company in his state. (There is only one producer of palladium in this country, a mine in Montana that is owned by a company in Russia.)