I've been trying to fix this issue for the last few days but I couldn't figure out how to fix it, so I'm reaching out here in hopes for a possible solution.
What I need to be able to do is add PointLight2D nodes to my scenes via scripts, however the following situation has been happening with all duplicated/instanced/newly created and even reparented light nodes and/or even if I were to perform the aforementioned operations with their parent nodes.
This is my test scene:

In it I have one natural light, and a light that's added onto the Node2D containing the godot icon sprite via the root node's attached script.
The TileMap has floors for the light to have something to be cast on and walls separating them. The walls have light occluders (so as to block the player's line of sight light).
The script attached to the root Testing node (type is Node2D) simply adds a newly created light and has this written in it:
extends Node2D
var point_light_texture = load("res://Assets/images/LightSprite.png")
func _ready():
var new_object_light = PointLight2D.new()
new_object_light.blend_mode = new_object_light.BLEND_MODE_MIX
new_object_light.texture = point_light_texture
new_object_light.energy = 2
new_object_light.texture_scale = 0.15
new_object_light.shadow_enabled = true
self.get_node("Node2D").add_child(new_object_light)
For the player scene, I have 3 lights:
A surrounding light

A shadow light:

And a line of sight light:

Here's a video of me moving the player around the scene: