Computing the volume of a region bounded by polynomial inequalities

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I am interested in computing the volume of the following region, as a function of $X$:

$$\displaystyle \{(x,y,z) \in \mathbb{R}^3 : |x|, |y|, |z^2 - 4xy| \geq 1, |xy(z^2 - 4xy)^2| \leq X\}.$$

This region is bounded and closed, hence compact, so it must have finite volume. Does anyone know how to do the calculation?

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The region is symmetric with respect to the joint symmetry operation $x \to -x$ and $y \to -y$, and $z$ appears only as a square, so there are only two octants you need integrate, e.g., $x>0, y>0, z>0$ and $x>0, y<0, z<0$.

Incidentally, here is the region for $X = 4000$:

enter image description here

It is an ugly integral, but simple to perform numerically for fixed $X$ (and which gives for $X = 4000$ the value $2813$).


I'd be interested in how this problem arose.