Active swap on a stock Android? Swap that shifts as much as 11 GB? What??
Get Terminal Emulator, do the following -
df > /sdcard/df.txt
mount > /sdcard/mount.txt
View txt files on pc with WordPad, not NotePad.
That will show the filesystems and their allocations, and then the mount points for everything used in the partition table.
I know that it's obviously heresy to suggest it but I'll say again - I doubt that SD Maid is telling the truth.
The commands I've provided will tell you the truth, the whole truth, and nothing but the truth.