M.P.
Next time you know to start out with small loads. There needs to be room for the bedding to move around so that the water can push thru every square inch of the fabric. When the bedding is crammed together there is no where for the vomit to go. It stays, in a diluted state, in the fabric.
And, rinse out as much of the vomit as you can before putting them in the machine.