I really don't know and think there is no definitive answer and it depends on the IRS agent.
For example..you do a mystery shop that makes no sense alone but is near your son. No sense to logic. Seems you can get dinged.
Kind of like shops that reimburse you $15 for food, fee payment is $5 and mileage is $10.... how does THAT work?
I wish there was a hard and fast rule involving the minimum wage like the above shop you HAVE to claim at least minimum wage and not negative income or else logically you wouldn't do it repeatedly... So, it has to be $7.25 or whatever it is now claimed...the end ..and not negative $5.