Some thoughts:
First, whatever floats her boat. If she enjoys it and has the time/motivation, go for it while she can.
Second, 26 miles at sub 3 pace is not a difficult effort for her if she is even reasonably fit. I have to imagine she's in sub 2:40 shape, so essentially that's just 7 straight weekends with a decent long run.
Third, she's probably getting some sort of appearance fee at some of these races (presumably the US races, at least). Might as well get paid while you can.
Fourth, I'd be curious to hear what her doctor says about doing that much mileage on consecutive weekends given her reconstructed knee.
Fifth, watch for her to transition into some form of ultra running (trails maybe?) if she still has the racing itch.
Good luck to her!