New Mom

Hello out there. I recently rescued a handsome young boy who only has the use of 3 of his legs. He has all four still there but his previous owner apparently decided it was better to let the broken leg heal on its’ own than to have it fixed. The doctors tell me he is not in any pain but I still worry constantly.
I am in desperate need of your help out there. The doctors think that POSSIBLY with two surgeries and about 20 weeks of recovery, he may have the use of the leg back but nothing is a guarantee. What should I do? Should I try the surgeries and pray that it works? Amputate the leg and let him thrive on three legs? Or should I let him keep the bum leg like it is?
Having only three working legs does not slow him down a bit! He is incredibly playful and energetic and loves to play with other dogs and go on multiple walks every single day.
As you all can imagine, he is part of my family and I want to do what is best for him. Any advice would be greatly appreciated.
I apologize in advance for him not having three legs but I hope you let us be a part of your Tripawds family.