“Does “subhakinha deva realm” cover the brahma realms, too? I know that sometimes the word “deva” means all beings above the human realm.”
Yes. Sometimes deva and brahma realms are clumped together as “deva” in many suttas. In the Dhammacappavattana Sutta, beings in all realms above the human realms are referred to as “deva realms”; see #6 in “Dhammacakkappavattana Sutta – Introduction“.
In “31 Realms of Existence“,
Subhakinha is listed as ““subhakinha deva”.
– But clearly it is above the deva realms in kama loka.
We just need to keep this mind.