F holes, spot the difference Also, it's not unthinkable that a job like this could be done without taking the top off. A real amateur may have worked that way. There isn't the slightest attempt of even fake purfling.
What kind of major bass bar problem would have required the replacing of a 38mm wide strip of the entire top? It's a Neuner and Hornsteiner viola c.1870 by the way. Thanks so much in anticipation folks!
I think Jacob is right it's not a crack but a parting of the ways - harder to fix I'd think. The bigger picture attached. The 'parting is only the bottom 4 inches or so. And thanks for all the comments!