Sechel, what did the child swear to? I think you’re referring to a תינוק שנשבה, a captured child. That’s spelled with a ה.
Whether or not all, most or even any secular Jews today are considered tinokos sh’nishbu is a a machlokes. Some say that most are – but that doesn’t mean that they’re good Jews. It means that they won’t burn for their sins.
Where in kiddushin does it say that a person who serves AZ is called a beloved son of Hashem?
A sinner who shechts does not usually render meat treif. Why is that a barometer for what makes a person good? That’s so arbitrary.
It’s a sad day when a person who claims to be a Torah jew can’t use Torah observance to determine what a good Torah jew is. The only issue is that it runs against the brainwashing in chabad.