What’s the best way to address dried urine in cracks on bamboo floor

Use an enzymatic cleaner and let it sit for a bit to consume the urine. A commercial product called Consume works very well, but there are some for pet urine at the pet store.

Ask at Pet shop for spray......

Hello, Mr Urine! Just kidding. To get rid of stain or smell? For smell, mix 50/50 water and white vinegar, spray or pour over area, let sit awhile, then blot up as much as you can with paper towels. Sprinkle baking soda over it, leave til dry, vacuum. Or yes, buy an enzymatic cleaner at most grocery or hardware stores.

A black light will show if it's all been removed (if you happen to have one). I have a Green Machine that works wonders.

Thank you, John

SOX is available at the pet store, you could spray that on and let it sit, then rinse it gently with clear water.