Saturated Roof Deck.

We recently moved into our home. It is a family home that has experienced a moderate amount of neglect and needs repairs. When we moved in it was summer/fall and the roof was leaking in several areas like Swiss cheese. Having a shortage of “slush funds” at the time meant an temporary solution. We installed brown aluminum roofing over existing 2 layers of shingles. Only in the areas where we were experiencing leaks. However while doing demo in one of the effected rooms we can now see the roof deck is saturated to the point of dripping under these areas. The house is a one level ranch with crawl space, all HVAC and plumbing are in the attic space. All ventilation for bathroom vents out roof. 4/12 pitch with no ventilation in attic. No ridge vent, no soffit vents and no eve vents. There is rolled fiberglass insulation, no vapor barrier. We were planning to do the whole roof when the weather breaks but fear metal roofing might not be the correct option?