Can I trust that bedbugs are gone after 3 professional treatments??

Backstory… A couple years ago, my good friend spent the weekend at my place & she slept on the couch as we don’t have a spare room. Well, she kept waking up with what looked like bug bites or an allergic reaction on her back & legs! We didn’t know what at first, but after the second night she told us she inspected the couch with her phone’s flashlight & found numerous bedbugs!! 😩 She took pics & showed us. This was a total shock since nobody in the apartment, including my daughter, had ever been bitten before & we’re on the couch all the time! Nor, had we ever seen any other signs of them! I was horrified & embarrassed! I apologized to my friend & she reassured me she was ok. After that, we bought bedbug sprays to spray the couch. We did that & vacuumed it multiple times. Several months later, she came for another visit, and AGAIN, wound up all bitten! This time WORSE than before 🥴😭 I felt so bad!! She left early, which was understandable! Awhile after that, we were able to have our apartment professionally treated. They did it 3 times, which is apparently more effective in getting rid of them. So far we haven’t noticed anymore signs of them.

Fast forward to now, it’s been a year since that last time my friend visited. She recently texted me asking how the bug situation was because she’s wanting to visit again since it’s been so long & misses us. I told her we had the apartment treated 3 times & haven’t seen anymore signs of them so I’m hopeful they’re finally gone. She’s willing to visit again & said if somehow they’re not actually gone she’ll make arrangements to leave early like last time. I said sounds good! That brings me to my questions, does anyone have experience with using professional treatment for bedbugs, or know anyone who has? Was it truly successful in getting rid of them? I miss my friend so much & don’t want her to go through what she did the last two times & end up having to leave early again 😭

Also, before anyone asks, we know that she didn’t bring the bedbugs here with her, because neither she or anyone in her house had been getting bit any time before or after the times she was here, and she didn’t find any bedbugs at her house.