If the textured surface is sealed, yet still traps dirt - this can only mean the sealer is one that does not provide a glossy surface. The dirt is getting trapped in the texture of the surfacing.
So long as the surfacing and grout are sealed sufficiently to bead water, you can solve the problem by coating the floor with "Lifeguard" or "Tile Cover". This will create a level of gloss that keeps out dirt and makes for easy maintenance. "Tile Cover" is a lower gloss level than "Lifeguard".
Lifeguard
Tile Cover
Note:
Sometimes cleaning is a trial and error process. The cause of the problem might be different than thought, or have multiple causes and results that must be handled in steps. In rare cases, it cannot be cleaned. Proceed as though it is an experiment whose results must be evaluated.
Any Aldon cleaner has more than one purpose. It is not limited to only this cleaning project.
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