Clearly you've never taken a course in economics or wouldn't ask such a question.
Try reading the question again. The lack of welders or Scotch today (TODAY) can’t be fixed by the market. The scarce resource can only be allocated by the market.
It’s absolutely not true, as you stated, that the labor available today can fit the available openings, if it only weren’t for the greedy capitalists who only want to exploit labor.