The source said Ladd agreed to terms with the KHL club but didn't finalize the deal, having a change of heart due to family reasons.
The 26-year-old would have been the second Canadian-born player to join the Russia-based league since the beginning of the NHL lockout last month.
Fellow Winnipeg forward Evander Kane made his debut with Dinamo Minsk earlier this week.
Ladd had 28 goals, 22 assists and 64 penalty minutes in 82 games with Winnipeg last season.
A two-time Stanley Cup winner, Ladd has 120 goals, 138 assists and 283 penalty minutes in 484 NHL games with Carolina, Chicago, Atlanta and Winnipeg.
"There's a verbal agreement right now," Pavelski said. "That's the plan, don't see anything going wrong."
Information from ESPN.com Pierre LeBrun, ESPN The Magazine's Craig Custance and The Associated Press contributed to this report.