Raquia doesn’t simply mean expansion, it’s used to describe by analogy the process of beating metal bowls into shape. This intention is affirmed in Job 37:18 “Can you join him in spreading out the skies, hard as a mirror of cast bronze?” one of many such verses indirectly making it clear they believed the sky to be a solid dome.
I’d sure like to know which scientific theory you believe postulates that the universe is surrounded by water. I’m not sure how it applies here though as the authors of scripture weren’t aware of a cosmos outside of the Earth, Sun and Moon, with stars being lights embedded in the firmament and the Sun and Moon moving about within it. This makes sense of verses later on describing stars falling to Earth in the end times, something which could happen only if stars were much smaller than they actually are.
A universe surrounded by water does not have pillars holding up the Earth, or the sky. It does not have storehouses in which sleet and snow are kept pending cold weather. It is how you personally reconcile discrepancies between ancient Hebrew cosmology and science. Ancient Hebrew cosmology is in fact a thing, if you google it you can choose any scholarly source (i.e. not apologetics ministries) and they’ll tell you what I have. Even William Lane Craig agrees this was the cosmology described in scripture, disputing only whether they sincerely believed in it or considered it mythical.
But this is all secondary imo, let’s get to the heart of the matter: Suppose there’s a group traveling about your area, led by a charismatic speaker who claims the world is ending soon. He promises he alone can save you, but you must sell your belongings, devote your life to him, and cut off family members who try to stop you.
He may also assign you a new name / identity, advise you to leave your home and job in order to follow him, and says that if you don’t love him more than your own family then you’re not worthy of him. His followers wrote a book about him in which he performs many miraculous feats, but no contemporaneous outside source corroborates these claims. What sort of group is that?