Is there really such a thing as forcibly booking someone on an oversold flight?

For example an unaccompanied minor misses a connection and there is only one more flight, oversold, out that evening.

For example, people volunteer to be bumped and are promised the next flight but when they select the volunteers and do the bump, the seats on the next flight are gone.

Do/Can they book the affected travelers anyway, print boarding passes for them immediately if all the boarding passes weren't already printed, and worry about asking for volunteers later on the over-over booked flight?

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