I'm back home, decent computer and connection, and I could finally download them. Hundreds of pages!
Confusing at first, the headings öf the pages in both WO116 and 117 is "Examination of Invalid Soldiers on (date)". They must have had just one form, one book for the regular check-ups on discharge and the other one for the real medical cases.
William Bennett is indeed listed on WO 117, on 22nd Feb 1876, with two others of the 108th. His description and a very clear summary of his career in the 14th and 108th. No injuries etc.
Interesting read, a future residence is mentioned with just one of the men of the 108th: Kurrachee, India. After having come all the way from India to Netley!
William Bennett doesn't appear in WO 116 in between the gun shot wounds, varicous veins, tuberculosis and fractured legs.