Simon, the small forward who spent three months at the club last year before earning an international rookie contract, arrived back in Australia last Friday night after going home before Christmas.
"It's been a bit of a story within itself at the footy club," Richmond midfield coach Danny Daly told AFL.com.au.
"I don't know 100 per cent but [the delay] had something to do with his visa and the amount of stay he had over here previously.
"It was about when he could come back and who was going to sign for him to come back.
"Once that was all sorted out, it was just a matter of him getting on the flight and coming over.
"Thankfully it was all resolved."
Simon trained away from the main group on Tuesday as he begins his efforts to rebuild his fitness base, which took a hit while he was at home.
Daly said the powerful 172cm Simon would need four or five weeks of conditioning before he joined in full training.
He also said the Tigers were confident the visa issues had been resolved and Simon should not encounter further problems.
"As far as I'm aware, that's it now, once he's over here it's all done and dusted so he should be pretty right from now on in," Daly said.
"It's a good story to get someone from overseas and see how they go."
Jennifer Phelan is a reporter for AFL Media. Follow her on Twitter @AFL_JenPhelan.
