Quarantine sucks big time so I decided to dig deep into this and found the following solution:
I removed the flatpak/flathub install, tried reinstalling from the command line and the problem was still there. I used Google to find where those errors belong and from there on tried the easy solutions. Now it works fine.
dnf reinstall libttommath
That solved the libtommath error. Next was the libboost_chrono.so error.
dnf reinstall boost-chrono
Solved it. Next up was the libboost_random.so error.
dnf reinstall boost-random
That fixed it. I guess something went wrong with the original install.
Anyway. qBittorrent works fine now.