A key prosecution witness against Theranos founder Elizabeth Holmes told her judge Monday that although he visited her home months after her fraud conviction — an incident Holmes is seeking to use as grounds for a new trial — he stands by the testimony he gave in her trial. Holmes is scheduled to be sentenced Nov. 18 on four counts of felony fraud, after a jury in January convicted her of defrauding investors in her now-defunct Palo Alto blood-testing startup out of more than $144 million. Legal experts say Judge Edward Davila will likely hand her a multi-year prison sentence. Early in her fou…