But to sack up to 6000 crew
....where did you get the figure of 6,000 from?!
I don't for one second think Walsh will sack EVERY striker. I suspect the company is clever enough to have monitored places like Crew Forum, the Bassa forum and other mediums to determine who the "trouble makers" (in their [the company's] opinion) are.
Sacking ANY of the strikers will, depending on how Unite/Bassa handles the next ballot, be illegal. So there's nothing more stopping Walsh from hand-picking certain people he really wants to get rid of and then dealing with the court cases (or letting Mr. Williams deal with the court cases) in a few years.