Hie! I'm not sure about Gombe,Kinshasa, I'm in lubumbashi and sometimes in kolwezi,
How ever, check the orientation of the company you are going for if it is angophone or francophone,pole around are so accommodative,
For me French is the most difficult Lang. to learn.
With $2000 and accommodation, yes you can manage depending on your social class.
Hope u're answered.
Mada.P