No I dont think the clowns are the cause of the problems here. The neon and the babies could be because they are so fragile. The tigers is anyones guess, I had clowns with my tiger barbs and the dern clowns thought they were tigers for the longest time. They would pack up with them just as if they were tigers themselves.
What did these fish look like when they died? Was there anything unusual about their bodies Any injuries
May have been a case of old age with the tigers.....Any help would be great so we can figure out why