It seems to me that the main difference with work on Chol Hamoed and work on actual Yom Tov is that you may not work on Yom Tov no matter what (I’m talking about life and death situations). However, on Chol Hamoed, if it involves a major loss (meaning not just the days’ salaries but loss of job or a huge amount of money like a business transaction that can only come about by doing it then etc. ) you may work. But it is not so simple that you can work if it is convenient that day.
Keep in mind that being mevasa a yom tov is compared to serving Avoda Zara so think twice.