Air Flow/Ventilation for Metal Roof on Mobile Home

I have a 18' x 60' Mobile home. A year or so ago, a contractor installed a metal roof over my existing shingled roof (without slats). This installer REMOVED the vents (bathroom/attic, etc) from the top of the trailer and COMPLETELY covered the entire top of the trailer with the metal roof.

Now, I KNOW i have ventilation issues in the attic because around where my bathroom & laundry vents are INSIDE the trailer it can tell they are just venting into the attic & that the humidity in the attic is NOT getting out of it.

I live in Louisiana where it's ALWAYS humid as crap down here.

I had to hire a different contractor to come back to put 2 -
Roof Vent Covers Exhaust Flow on each side of the mobile home. That has somewhat helped; however, it seems like all of the hot attic air in ONLY coming back into my house.

Could you help with the best way to go about fixing the issue? Would it be to install maybe 1 or 2 electric roof vent systems since my home does not have any gables to put that type of vent on it?