You might have solved it Morgan but here is a suggestion in case you haven't...
I suppose you work on your fullscreen swiper as explained here:
So, include your swiper component inside a d-block with position-fixed class
Fow example:
<div class="container-fluid py-3 position-relative">
<div class="d-block position-fixed top-0 start-0 w-100">
<div is="dmx-swiper" id="swiper1" style="height: 100vh !important; " autoplay="true">
<!-- your slides here (static or dynamic) -->
<div class="swiper-slide"></div>
</div>
</div>
<!-- here you add the content that you need to go on top of the swiper inside a container, section or whaever your structure requires... -->
<div class="container">
</div>
<!-- OR -->
<section>
</section>
</div>