I also have two dogs.  While every dog is different, I found that mine were very careful of each other, first when the female had cruciate repair over the summer and now as the male went through amputation and is going through chemo.  They could clearly each tell when the other was hurting or weak.  You might have fewer issues than you think.  And, until the staples come out, Eider should only be out on short leashed potty breaks.  He will sleep a lot so the bionic tail probably won't be much of a problem.  In terms of the boxer shorts, the surgeon will probably send Eider home with a come of shame and strict instructions to wear it until the staples come out.  The cone was a challenge for some of our dogs.  Otis is a front leg amp, so we wore a TShirt (with excess material gathered in a hair tie) instead of the cone.  Worked perfectly to keep him away from the incision.  I suspect the boxer shorts are the equivalent for the rear leggers.

You might want to consider a log book so you can keep track of meds, food, water, and business for the first 2 weeks.  It is especially helpful if more than one of you will be giving meds.  I also found it helpful to know when (ok, in my opinion) Otis needed to go outside and when it could be optional if he didn't want to get up.