They’re swearing to god that what they are saying is true. It’s phrased a bit awkwardly, I think they’ve mixed up “I swear to god” and “hand on heart” or maybe “on my mother’s life”, something like that.
1000 roaches or a human in my attic is not what fucked me up, it was that damn second comment and I scrolled furiously thinking surely it's not just me. Thanks for the explanation.