It's probably important to know what kind of photos they are, i.e. ink jet prints, dry, wet lab etc. If it's ink jet then I'd assume that using any kind of liquid cleaner will mess up the photo but that's just a guess.
Dye sub prints put a gloss coating on the prints so you could probably use a mild cleaner and this may be the same for digital prints that are non-wet lab. I don't know enough about wet lab to comment.
If using liquid cleaner I'd recommend putting it on the cloth first rather than directly on this print no matter what type of photo it is.
Perhaps you can get some test prints done using the same printing process and experiment before trying it on the real photo?
PS. Don't use wirebrush and dettol btw.