I dont understand having 3-4 farms and having a problem getting specific train passengers. I have 2 farms, send out my personal train every couple hours, plus the eggexpress comes every 6 hours with 14 passengers. Plus I have 6-8 neighbors who set out passengers regularly.

My advice, is not to do mystery tasks. I opt out of that derby cuz my nh only does 400 point tasks. I certainly wouldnt be spending diamonds like that. Too expensive for me.