what nvidia card is it
nvidia is killing off support for old cards
is it a built in nvidia laptop "chip" on the mobo
in order to use the "plymouth" bootscreen you HAVE to use the nouveau driver
the fedora fancy splash is EXPLICITLY coded to use that driver
with the kmod-nvidia rpm you can set the the xorg file ( not used by default )
you said you "tried" the nvidia driver ( the kmod-nvnida.rpm???? )
and you DID rebuild the boot image?????
mv /boot/initramfs-$(uname -r).img /boot/initramfs-$(uname -r)-nouveau.img
dracut /boot/initramfs-$(uname -r).img $(uname -r)
now you say you went BACK to the "nouveau"
you will now have to rebuild the boot image TO USE the nouveau instead of the nvidia
remove the udev block
and possibly remove the "nomodset" in the boot line