Fans began speculating whether Maksim was injured or had a family-related problem, but an insider told People that his absence was a direct result of ongoing conflict with Vanessa, a 36-year-old TV personality and former beauty queen.
"There's a big chemistry issue," the insider told the magazine. "They both have big personalities and that's not always the best recipe for a good partnership... They've been fighting a lot."
"I wouldn't be surprised if Maks doesn't return as her partner for the rest of the season," the insider added.
Maksim's tweet, however, would seem to suggest he has no issue with Vanessa and is looking forward to performing with her again. If reports of a feud are accurate, then it's also possible the couple talked things out recently and buried the hatchet.
Speculation of conflict did surprise many Dancing with the Stars viewers to begin with, as Maksim and Vanessa appeared to joke around and work well together in rehearsal. The pair also received consistently high judges' scores for their routines since the start of the ABC reality dancing competition last month.
Vanessa and Maksim were also shown bonding over being parents, as Vanessa is mom to three kids and the pro dancer just welcomed his first child, a son, with Peta Murgatroyd -- who is partnered with Vanessa's husband Nick Lachey -- in January 2017.
In a Tuesday interview with Us Weekly, Vanessa said of Maksim, "I just know that when I'm on set he's my coach and I'm the student, so I listen a lot more and I don't speak up as much because this is a field I don't know. He's trained me and taught me so many amazing wonderful new things just like any trainer would or teacher would... It's been an amazing experience."
During Monday night's Dancing with the Stars performance show, a pre-taped package of interactions between Vanessa and Maksim was not even shown. Vanessa's entire segment featured footage of Alan and herself preparing for her guilty-pleasure jazz routine.