You were actually correct on the first part -- as part of their attempt to bust the strike, Kellogg's attempted to replace all of the striking workers, and tech

You were actually correct on the first part -- as part of their attempt to bust the strike, Kellogg's attempted to replace all of the striking workers, and technically they did. Critically, the striking workers weren't fired and are thus able to come back to their jobs without any problems. But the union absolutely did not give up -- they can't really control if the company brings in scabs. In the end though, the union won and got everything they were asking for, including giving back the jobs to the strikers.