No, there is no explorer for Blackbytes (Ergo privacy).  Sure, anyone can use blackbytes.
If you spend all or a part of your blackbytes and then recover your wallet to a point prior to spending the bytes, your wallet will show the prior amount; however, you now have a corrupted balance.  When you do this, you will lose more than just the part you spent and likely lose access to all your blackbytes.   If/When you do this, you will end up sending your wallet to someone like me to recover what can be possibly recovered.  I have done this for many people; however, I have basically stopped, because it's not worth my time.  I have to admit how cheap people are in that they are willing to spend many hours of time trying to recover $20 especially when it's someone elses time. 

So..... Don't do a recovery after an amount has been spent.   Hint:  Make a backup each time you make a Blackbyte transaction so that you're totally safe from loss.