I'm afraid I don't have anything to offer with regard to your concern. However I noticed you had yet to receive a reply to this thread. So I thought I would at least acknowledge it. Here are links to 8 articles, from PC's archives, that I thought might be of at least some interest. Hopefully there will be something in them that can be of some help:

What is Gaslighting? | The Exhausted Woman

Gaslighting: How a Parent Can Drive a Kid Crazy | The Exhausted Woman

7 Ways to Extinguish Gaslighting

7 Ways Narcissists Retaliate Through Children | The Exhausted Woman

How to help your children when their other parent is a narcissist

https://pro.psychcentral.com/recover...dium=popular17

https://pro.psychcentral.com/recover...dium=popular17

https://pro.psychcentral.com/exhaust...rcissistic-ex/