Well, remember he’s dead, and we have only his widow’s account of what he did and why. She’s probably not going to want to paint her dead husband in a negative light by saying ‘Yes, he knowingly gave someone who had stolen a large amount of money from her employer money to buy off said employer and a fancy lawyer who made him sign an NDA and agree to drop all charges.’
As other people have pointed out, the family-minded ‘No relative of mine is going to prison!’ is already a bit odd in that he’s a distant relative of Tim Walker, not a close family member of Sally, who would have been the one going to jail if anyone (I mean, why would he care?) and sits even more oddly with the high interest rate, even if he didn’t know the house was heavily mortgaged. And presumably the Walkers’ defence in court was that it was a personal debt, not a business one, so the collapse of London Man’s business shouldn’t affect them.
I’m not suggesting that ‘Rebecca’, the man’s widow, is lying about the actual finances, only that she’s unlikely to want to say her dead husband helped a known thief to evade justice and hush up her crime, and then made very tough repayment terms. Who knows what his real motive was? I suspect there’s a bit of fudging going on there, too.