The student-athletes, both 21, were part of the final South African women's training group which attended the camp under the guidance of national coach Delaine Mentoor.
Mentoor, who is also the Madibaz coach, said Maartens and Vaughan were among those who made the cut after the first round of trials in Stellenbosch in December.
"This was a camp for the final squad selection for the national team, which will be announced in April," she said.
In an Olympic year there is plenty to look forward to, but both Maartens and Vaughan said they would first focus on what they learnt.
"I really enjoyed the camp, which helped to determine how far we have come in training and to see what we need to work on," said Maartens, a fourth-year BA student.
"We started the weekend with a fitness test and then played matches. These were very helpful as I could see what areas of goal-saving I need to work on such as bounce shots and lobs."
While she eyes the Tokyo Olympics, Maartens has other goals too.
"I also want to focus on doing well at the USSA (University Sport South Africa) and Currie Cup competitions, where we will be representing Madibaz."
Vaughan, a third-year pharmacy student, said the camp was a "big learning experience".
"I'm constantly working towards improving and playing at the highest level that I can. It gave me an opportunity to figure out what I need to work on.
"There's always something new, whether it's a move or a play in the game. Fitness also plays a role in your ability to fulfil that."
Both players are appreciative of the support they have received during their water polo journey at Nelson Mandela University.
"Delaine [Mentoor] is very important to me as she has coached me since U15," Maartens said. "I can really say that I would not be the player I am today without her constantly motivating me."
She also acknowledged the impact that Madibaz Sport manager Melinda Goosen and coaches Jonathan Watkins and Luke Manthe has had on her development.
Maartens also paid tribute to teammates and "training buddies" Vaughan and Yanah Gerber.
"They motivate me on days where motivation is lacking and we constantly remind each other that we aren't doing it for ourselves. It's also for our teammates in the Olympic squad and the SA water polo women's programme."
Vaughan, who strives "to be better than before and to never become complacent", acknowledged the role of Maartens and Gerber as well as family and friends.
"They have driven me to work hard. There is always room for improvement."
Mentoor, a former SA star who took the national coaching post in October, said the camp had proved an excellent gauge of the players' potential.
"In game one we could see the ladies were rusty, which is understandable due to Covid but, as the camp progressed, they quickly found their rhythm and the level improved all the time.
"It was great to see our Madibaz players competing among the best and holding their own. I wish them the best of luck for selection."