Lee faces a heavy punishment after being found guilty of match-fixing charges involving seven games between 2008 and 2009. He faces being banned for life when governing body the WPBSA deliver their verdict on Tuesday.
Lee won his first professional title in six years when he defeated Robertson 4-0 in the PTC Grand Finals in Galway last March, but faces being thrown out of the sport only 18 months later.
"That is important as a deterrent," said 2010 world champion Robertson.
"We have to show zero tolerance on match and frame-fixing. There is no other option than a life ban.
"There may have been players offered things in smaller events, and this should cut all of that out.
"I am not sure how this verdict can be damaging to the sport in the long term. A guy has been found guilty of cheating and faces a life ban.
"And that comes after he was suspended for almost a year. It gives me confidence that the governing body are doing it thoroughly: these are hard cases to prove.
"There will be no-one taking risks or trying to nick a few quid on the side because the authorities can see everything.
"You don't want to be tarred with the same brush, by association. But it is a difficult sport and pressure can make you miss shots, that's why it is so hard to prove."
- Sports & Recreation