those last two lines if the journal lead me to suspect it has something to do with the arch kernel
but you say it suspends normally when using the gnome DE so perhaps compare logs between the two and see if those lines are present with gnome as well.
another thing you could try is to disable the freeze option, as i’ve found issues with that on certain motherboards.
edit your /etc/systemd/sleep.conf or whatever arch uses in its place
uncomment the line
# SuspendState=mem standby freeze
and delete the word freeze