Ox, I don't know your whole situation outside - septic or city sewer nearby trees, etc., but some comments:
1. Those don't look like palm roots. Could be, but I doubt it.
2. If roots are here, then there is a crack or leak somewhere that allowed them access. Roots will find and follow the moisture, they don't break thru pipes to find it. Problem will return and likely with a vengeance. See number 4. Your video mentions it coming up between the foundation and the pipe. Either way there has to be a seal or else.
3. Someone mentioned RoundUp. Not the thing here since RoundUp/Glyphosate is absorbed thru the green foliage to be transmitted to the roots system.
4. Over simple solution to describe, not always easy to do: along edge of house near where bathroom is, test for roots going under or into the toilet drain. You can cut off the larger parent root to kill any roots beyond that under the house.
I didn't know that. So I Googled it. Well, it turns out that RoundUp can, and will, effectively kill a plant via root absorption.
Here's the text I got from
The Effect of Glyphosate on Tree Roots :
Glyphosate
Glyphosate is an organic, high-phosphate compound widely used as a broad-spectrum herbicide to kill unwanted plants of many different types. It is usually diluted in liquid and applied as a spray directly on the weeds' foliage. When it contacts a plant, the compound is taken up by its roots and foliage, where it blocks an enzyme required for plant survival, eventually causing it to die. During spraying, glyphosate also comes into contact with soil. It binds strongly to soil particles and can remain in the ground for many months, according to Cornell University.
Tree Roots
Roots serve many roles in supporting all plant life, including trees. They take up water and nutrients from the soil, allowing them to move into and through a tree's transport system to reach all of its parts. According to Utah State University, when glyphosate is applied to an undesirable plant and kills it, the dying plant releases some of the chemical back into the soil through its roots. Tree roots in the area can take up some of this chemical, either by contact with the roots of the dying plant or by directly taking up residual glyphosate from the soil.