I am working on this bench carved from a solid red oak log. I scorched it five time with scrubbing between each treatment and now I applied 5 coats of linseed oil to seal in the carbonized wood and prevent people from staining their cloths but I have the pictured mold/fungus which keeps innig back through all the treatments. Does anybody have an idea how to prevent this from coming back. I am working on this piece is in the NY state Hudson valley.

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Linseed oil is the culprit. It is an oil that bacteria/mold/fungi like to eat. Stop feeding them.
Even without adding anything, fresh wood has sugars and other things that microbugs like to eat. The moisture will support the mold. Sunlight will kill it.

If by 5 coats of linseed oil you mean natural flaxseed oil instead of boiled linseed oil, then you've got a ton of oil that won't dry. Red oak is so porous there has to be raw oil laying down in the wood unless you went several weeks between coats.

That is correct, I wait usually about a week between raw linseed oil coats. I also delude the raw linseed oil a bit with natural turpentine. I feel the many coats are needed to prevent staining form the carbonized wood.

The evidence of the dark staining in the heart of the wood seat area shows that fungus is present in the log. I am surprised that the fungus survived the charring process. It is more than likely that what you see is the fruiting bodies of the fungus living in the wood. It may take years for the log to dry enough to inhibit the fungal activity. Are these pieces intended for indoor use?
I'm not a fan of linseed oil. It may be old school but it has none of the properties I would want in a finish; durability, water resistance, fast curing, oil resistance etc.

Yes Tim, it is intended as an outdoor piece. I chose the linseed because I believe refinishing after environmental wear is easier. On other similar pieces where I used a an exterior clear varnish over the charring, refinishing is problematic after some wear. Tests have shown that with linseed oil I can just charr the damaged area again and refinish with linseed. Plus the Linseed supports the natural sheen look of the carbonized wood better, With varnish I have to strip everything down and start all over from new including the charring. And while that usually is not a problem, I do loose the expressive look of the chainsaw cutting and the left over “live edge” from the original log. What finish would you suggest to use on charred wood for exterior use? On the Seat part I use an exterior grade clear varnish because it also provides UV protection and inhibits the greying over time.

There is a thread recently on appropriate finishes for teak furniture that mentions some penetrating finishes that may be compatible.
I would also look up the Japanese practise of charred wood finish - shou sugi ban. There are surface treatments used to maintain the char.