What makes this worse to me is that you are being subject to the local Elders interpetation of Watchtower rules
In my area two young JW's in the past six yrs have committed suicide . One had a memorial service at a funeral home with an Elder as the speaker . The other had a Kingdom Hall memorial with two Elders giving the service . In both cases it was stated the deceased was clearly depressed and took their life out of desperation, and that we must realize they had an illness . Witness family connection also played a part I am sure . The first family had no other witness relatives .The second one had half the congregation related to him and many of the servants were relation .
I hope your nephew gets a respectful service no matter where it is held . My sympathy goes out to you and his family . It is so difficult when someone dies this way ,and you are left wishing you could have done something for them .