Cargo hold is "somewhat" ventilated, hatches are not air tight. But this is beside the point. What is important, is whether the compartment is big enough for heat dissipation. Also, do you have enough clearance from other objects - as prescribed by the manufacturer. There should be "some" indications if not for this, then for a similar controller.
They usually put cheap off-brand controllers in those kits, that nobody buys on purpose and nobody knows about. But, if you tell its Amp rating, we'll tell you how "close" to battery it should be, and with what cable, and how much clearance, more-less. Proximity to battery depends on the cable.
IIRC, my 30 Amp MPPT requires 6" clearance from top and bottom and is not recommended to be installed in small enclosed volumes like closets.
Edit - PS:
Disregard controller Amp rating for battery cable calculations if you won't be adding more panels in future. If this is a PWM controller, you only need to know Isc of this 200W solar array.