This is a turkey and it normally is perosis and it is almost always caused by poor nutrition such as feeding a chick starter instead of a proper high protein turkey or game bird starter. Chick starter does not have the higher amounts of protein, lysine, methionine and niacin that they require for proper development at an early age.I would agree that the poult should have a chance to live, as long as it can get enough nutrition, and is not being picked on by others.
Leg bone deformities such as varus valgus deformity, tibial dyschondroplasia, or rotated tibia are very common in meat birds, and may be misdiagnosed as slipped tendon. Slipped tendon is usually more evident at hatch. Here are some good articles including good pictures of various deformities which usually cannot be treated:
https://www.sciencedirect.com/science/article/pii/S0032579119479595
https://www.researchgate.net/public..._of_the_Intertarsal_Joint_in_Broiler_Chickens