That's right. Latex water-based paints may dry in only a few hours, but they coalesce for around two weeks (the curing process). Until the paint is completely cured, it can be damaged by humidity.
Even if the paint is free, using improper topcoat is shooting yourself in the foot. You'll apply free paint and primer at $30 per gallon, and in a year or less it is peeling. You'll then get to spend hours scraping off both the topcoat and primer, pay $30 per gallon for paint and primer again. So, you've wasted the first primer purchase, the labor to apply and strip the first paint job, and the free paint that could have been used elsewhere in your house.
Case in point - doing the job right the first time with the right materials is cheaper, hands down. If you can wait to install the paneling, wait to use the bath, or prevent the paneling from getting wet, you should wait to apply paint until you can get something that's meant to be there.
Wall Paint - Beauty on a Budget
Wall Paint