To charge a battery the voltage has to be higher than in the battery.
Unfortunatly wind generators deliver less than they promise and the cheap
ones even less.
If You donīt use them in winds 15 mph up I doubt You will see any results.
Since You say the batteries are holding the charge the wind gen seems to be the problem of concern.
Connect a light bulb IN LINE between the wind gen and the charge controller.
Afterwards connect a light bulb IN LINE between the charge controller and the batteries.
To get an idear of what Your wind gen can do for You install an AMP METER IN LINE between the charge controller and the batteries.
Observing it will indicate if You produce any "usable" energy and how much.
The charge controller adapts the energy produced by the wind gen to the battery voltage.....here it should be mentioned that charge controllers also need energy to function and some low quality ones need quiete a lot. There for they draw energy from the battery EVEN IF YOU DONīT PRODUCE.
For reliable energy on bord I recomand high voltage solar panels
together with a MPPT
charge controller with cooling
by heat sink and NOT COOLING
FAN to get max efficiency and reliability
Hardly any maintanance, nothing can break and NO noise
Unless the sky is totally covered You will produce usuable energy to charge batteries ALL THE TIME
If space is an issue, flat and flexible solar panels
con be installed temporary on many surfaces like cabins and dogers with bungys or velcro.