Hi,
Well the acid in the urine won't do the tape much good.
You could try this [https://lunchmeatvhs.com/blogs/blog/rescue-your-awesome-analog-treasures-from-moldy-malfunction-with-help-from-tapehead-chip-parton|method] at least to get it clean enough to get it working so that you can make a copy.
I realize that it is for a video tape but the principle would be the same. Might depend on how important the tape is.