If you could get his shareholding down to 20%, you could possibly arrange purchase of the company by another entity and compulsory acquire the 20% shareholding.
Firstly, you need to remove him as a director. Then possibly look for additional investment in the company hopng that he does not participate and thus diluting his shareholding to 20%. Then sell the company into a new shell company at market price.
Obviously you'd need to get a solicitor & accountant to look at how this can be done properly & above board, but it may be the only solution.
Link to article from lk shields on something similar
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