Collision meshes of the ankle not accurate

Hello, I have an issue with the approximation made for the collision geometry of the ankle_X joint.

This configuration is collision free according to the current urdfs (tested with all 4 urdfs available).

This is the collision geometry tested for the ankle_X joint. There is a mesh file "ankle_X_collision" in the package, which is not used in the urdf file. Using this mesh file instead of the box give the following geometry :

Which is correctly detected as in collision.

Why did the use of this mesh was commented and replaced with a box ? Should I commit this changes in the main urdf or another one ?

EDIT : here is a "valid" configuration according to the current urdf, which is obviously in self-collision : q=[-0.07371432604417776, -0.25022428805674013, 0.9318755416181825, -0.0004259847262110303, -0.00038109759515798404, 0.05982600533934256, 0.9982086567380454, 0.5519171789948055, -0.12430793696215368, -0.5552120067242478, 1.2987498545951066, -0.743368598286438, 0.12544749852275638, -0.12843963521888768, 0.5111938617621895, -0.964350738781588, 0.5762332241895781, 0.3890754003134548, -0.5121084703203191, 0.0002105395264093808, 0.00849924757484463, 0.2638302767309955, 0.17566292242525705, 0.00063543299319741, -0.4939674222198186, 0.0002640574531312831, 0.0006876429792204463, 0.10532874305175034, -0.004945183546427389, -0.2625331918948741, -0.16949365039027733, -0.00626388221697223, -0.4886847139642828, 7.056667933752162e-05, -0.0018624601202724823, 0.10640676864984272, -0.005018372868773, -0.0002188055250994256, 1.3769155642407247e-05]