A missionary's challenge

So, what do you do?
The other day I found out that Janji "gave" one of his children (his son, about 10 years old) to a marabout (Islamic teacher) to study the Quran.  I have been teaching Janji since 2011 and he is excited about the gospel.  He frequently makes comments about Christianity's superiority over Islam.  Such as, "You missionaries do what you say and teach.  These marabouts say/ teach one thing and do the opposite." And "when I study God's word I have less of a desire to do evil and repay others for what they have done to me." 
So you can imagine my surprise when I learned from someone that he had "given" his kid to a marabout.  This usually lasts about 5 or 6 years and typically the kid is abused physically, emotionally and spiritually.  I am not exaggerating here. 
Last night I brought the subject up and explained that I wasn't pleased about this. 
First of all, if what he has told me is true why would he want to have his kid study the Quran?  His answer: because at least he is learning about God. 
Second, if he is truly believing the gospel then what his children are studying is important to me and I also don't want to see them abused.  His answer: this guy is really nice.  He gives me lots of gifts. 
Third, if he or anyone wants to learn about God that is what I'm here for.  Just let me know.  His answer: if you missionaries had started a class for kids before I would have sent him to live w/ you.
We are still learning a lot folks.  Please pray for us.  We didn't see this coming, but in hindsight probably should have.
I left Janji by saying that if he can get his son back (harder than many of you may think due to cultural reasons) and he wants him to study somewhere to send him to us and please don't give any more of your children to marabouts.  I also explained that it would be even better if Janji himself would teach his children about the Lord (we are not there yet in our teaching program, there is so much to cover) - this is thinking way outside the Jalunga box. 
Please pray for us all here.