That really is amazing that a vet would suggest a shoulder reconstruction based on an educated guess without any scans! I have had to deal with a number of orthopedic problems over the years and decisions need to be made after a thorough workup by a specialist vet with the appropriate scans - xrays, CT or ultrasound combined with your own research.
I just go straight to my specialsit vet who is also a friend and dont even bother with the general vet as they want to do x-rays and then you go to a specialist and they do them all again but often with better equipment and better placement.
Once you have all the facts then you can make decisions. In some cases surgery is the only option in other cases other options can be tried out before going down the surgical route.
Obviously it is always better if you dont have to go the surgical route but in the several occasions I have chosen that route it has fortunately worked out really well, they were both situations where physio and chiro didnt work because they were both problems that could only be fixed by surgery.
In other cases chiro has worked really well. This is where you need to all the information.