Srivaddhanaprabha claims that he himself helped the striker turn things around, threatening to run his contract down if he did not change his ways.
'I went to talk to him myself,' Srivaddhanaprabha added.
'I asked "do you wish to end your career like this? Do you want to stay here like this? We'll let your contract run out then release you. Don't expect a better career path."
'He said he didn't know what to do with his life. He'd never earned such a large amount of money. So I asked him "What's your dream? How do you think your life should be? Just think carefully about what would you do for the club. I invested in you, do you have something in return?"'
According to Srivaddhanaprabha, the pep talk had the desired effect, with Vardy becoming a 'new person'.
He has scored 22 goals this season, as well as making his England debut and scoring twice in six games for Roy Hodgson's side.
'After (the conversation) he simply quit drinking and started working hard in training,' the vice-chairman explained.
'His physicality wasn't as good as it is now. We know he had explosive acceleration, but we simply had no idea he could be this good. He's adapting, working on fitness training, he's turned into a new person. And that's better.'