Kendall, who fell in love with Joe on Season 5 of Bachelor in Paradise in 2018, was seemingly looking for more closure from Joe, even though the pair had discussed the demise of their relationship multiple times throughout Season 7 and had agreed to move forward with their lives.
"I don't have any resentment -- it was a little confusing," Joe, 34, told Us Weekly in a joint interview with Serena, 23, on Wednesday.
"The timing, I would say, wasn't the best. I was just really focused on Serena and getting to that moment. I had a ring in my back pocket. So it was more like, 'Okay, I get that you're here, you know, I wish you the best, but it's not the time. Now is not the time.'"
Joe added, "But, you know, I hope she's happy."
Once Serena joined Joe on the beach ecstatic about what was to come, Joe had to break the news to her first -- before opening up his heart -- that he just had another run-in with Kendall.
"I definitely feel the same way as Joe," Serena explained of Kendall showing up right before her marriage proposal from Joe.
The Season 25 The Bachelor alum continued, "I mean, I hope she's happy. I wish her the best. And, you know, we're just happy to focus on our relationship now and kind of keep those special moments between us and keep them private and special in their own way."
"We haven't heard from her since. I haven't heard from her since, so yeah," Serena noted.
Joe then quipped, "I mean, we're in Canada, we're going to go to dinner tonight, so hopefully, like, one of [Serena]'s exes doesn't show [up] at the table."
"I don't know, I think we need to even it out a little bit!" Serena joked in reply. "Maybe I'll make a couple of calls!
As for what's next for the happily-engaged couple, Joe admitted he and Serena will be "taking it slow" before they move in together in Spring 2022.
"We're going to focus on the move and just really focused on our relationship and let it happen," explained Joe, who said he knew he wanted to propose to Serena the night before they got engaged.
Serena, who was "shocked" about Joe getting down on one knee," shared, "We did things out of order. We're going to do the move and then, you know, maybe in a year we'll start talking about wedding stuff."
The self-proclaimed logical individuals apparently "threw logic out the window" on Bachelor in Paradise, according to Joe, who added, "Now we're bringing it back and taking our time."
Joe and Kendall both seemingly came to Paradise 7 for closure and to start new romances, but it didn't take long for Kendall to reflect on her past with Joe and lament about how they had broken up over logistics -- meaning Kendall wanted to continue living in Los Angeles, CA, and Joe desired moving back to his hometown of Chicago, IL -- despite still being in love at the time.
When Kendall stepped on the beach this summer, Joe was already falling in love with Serena, and so Kendall ultimately decided to leave the show because it was too difficult to watch and her feelings for Joe registered as painful realizations that she wasn't over him.
"If she really wanted me back," Joe said of Kendall earlier in the season, "she should have told me before I got here and before I started this. Because I really, really loved her."
Kendall even called Joe her "person" in tears on her way out of Paradise.
When Kendall surprised Joe before his marriage proposal on Season 7, she explained, "When I first came here, I knew you were going to be here. And part of me thought it would be really easy to come here and have a closure talk, and to work toward finding a new relationship and hopefully love, but that's not what happened."
She continued, "I came down on this beach and was completely, like, surprised by how it made me feel and how overwhelming it was. And I think ultimately, what ended up happening is, I ended up coming here to fully let you go."
Kendall ended her speech with, "I'm really excited for you and Serena, and I felt like I couldn't leave the beach without fully, like, expressing that to you."
Joe politely thanked Kendall, wished her the best, and called her "a catch" for her future partner, and then he needed a moment alone and a walk on the beach before reuniting with Serena.