At the time , using steroids /HGH was not prohibited in baseball. So admitting to its use had no legal repercussions. here's a guy who risked it all by testifying under oath that he didn't do it. he did not have to testify and there was no penalty for admitting the use. So why would he have stuck his neck out so far?
On the other hand , his sudden performance gain after going to Toronto makes you wonder what did he do?
Interesting set of facts.
As far as HOF goes , you will have to keep out almost a whole generation of the leagues best if you disqualify people for steroid use which , again , was not prohibited at the time.