Did you read the article?
It does say Verdugo might miss the start of the season, but it also says he also might not. Such is the nature of uncertainty. It also says Verdugo’s back was a factor in signing a Pillar, but that all 3 outfielders hit left handed was also a factor.
So far, there is no real reason to be concerned beyond Dr. Kevin Kennedy and his questionable medical credentials. If the Sox signed a higher quality replacement like Yasiel Puig, that might be a stronger indication of how little they expect Verdugo to play...