The common treatment for LCL rupture is to suture it back together. Given the description of the ACL by Griffin, Jr., and the reports of using a graft from the left patellar tendon, I think it's very likely that RG3 had Revision ACL Surgery on the ACL, i.e. replacement of a partially torn or ruptured graft with a new graft.
Comparisons to AD or Phillip Daniels are invalid. Neither Peterson nor Daniels had previously torn his ACL.
There are a lot of considerations with doing a second ACL replacement. For example, when a graft is done, there are tunnels drilled into the tibia and femur. Hardware (screws) is used to secure the graft. A revision surgery can vary widely depending on whether the original hardware is removed, whether a new tunnel has to be drilled (typically the case, but not always), and whether a bone graft is necessary to attach new hardware. It's pretty clear that Griffin didn't have a bone graft, but it is possible (especially given the increased length of the surgery) that a new tunnel was drilled.
The biggest concern for Griffin isn't whether he is ready for the opener, it's that that the graft is successful. He's got the most skilled doctor, he's young, and he's athletic. All that plays in his favor. However, it's worth noting that, while 90% of ACL grafts are successful, the rate drops to about 75% with revision surgery (This is for the entire population of orthopedists; Andrews' rate is likely to be higher but I don't know either way).
He really doesn't want to injure that ACL again, especially if he had to have a second tunnel drilled. While there are athletes that have returned from 3 tears in the same knee, the rate is low, and eventually you just can't drill tunnels in the bones anymore. It will all depend on the details of the surgery and his healing process, which was very good for the first injury, but I wouldn't be too surprised if they play it safe with him next fall and do everything they can not to rush him back.
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