I'm a thinkin' that mineral spirits will remove the hootus contaminant.
Soak a corner of a small rag and swab it on there. Scrub thoroughly, but not vigoursly. A vigourous rythmic scrubbing will just make the problem bigger. Once the contaminant is removed, the hootus will be afflicted with a tingling sensation from the mineral spirits. You will need to decide if this is a good thing or a bad thing.
To alleviate the tingling, wash the hootus thoroughly with warm soapy water. Again, avoid vigourous rythmic scrubbing.
The cumulative events of the purported hootus contamination and subsequent de-contamination may cause post-traumatic hootus stress syndrome. To date the latest theraputic measures and consultations have not been proven to be effective.
It seems the most successful treatment of this condition is to "soak it in cider".
Good luck Gerald...