Hi I’m in a similar boat, came to post and found yours!
If your dog isn’t limping now just from taking metacam then injury rather than rupture sounds plausible, so it might not be quite as bad as you think? Ours has a rupture now and has been on 3 legs for 10 days even with strict rest and metacam, but he has had issues in the past where he limped for a day or so then seemed fine with a week of anti inflammatories and no walks for 3 weeks.
If you have questions I’m sure the vet would be happy to answer them over the phone?
Vet also said that the other cruciate will go at some point in next 6 months, meaning he would need 2 ops... so hopefully the crate rest will avoid him needing either. My understanding is once they have a problem with the acl it’s something that will worsen over time and can potentially affect both legs.
I’ve searched other related threads on MN and there are a few so have a read through because theres good advice and things my vet never mentioned. Also it seems there will be arthritis in the joint afterwards and it can take months to heal depending how bad the injury is, with a very slow rebuilding of walks after the crate rest period is over. In effect, older dogs have had to be “retired” and can’t really manage walks over a mile again. Again it depends on the severity so may be worth a chat with the vet to decide on the course of action.
We’re only a few days in and each day the progress seems different, sometimes he holds it up all the time, sometimes he tries to put it down intermittently, but that’s still more than he was doing last week when it happened. He’s on metacam and it seems to knock him out thankfully because he’s usually so active. I just wanted to try this route and get him to a point I can get him to hydrotherapy as that’s supposed to be really good for this type of injury.
You have my full sympathy, it’s awful to see them struggle, fingers crossed for both of them!