Domain Expansion pack, need help with making Domain inescapable

so im working on a little project solely for fun and getting familiar with datapacks and the api, and ive run into a wall.
the basic gist: ive added a skill that allows you to create a roughly 16 blocks wide sphere out of particles that gives others inside it certain potion effects such as weakness. now, i want to make it impossible to just run out of the area. one idea i had is to simply execute as an armor stand placed in the middle of it and tp players 0.2 blocks towards it if theyre 8-9 blocks away. though im unsure if this is possible.
my second idea was to use the armor stands i use to create the effects. theres 36 in total, one for each 10 degrees of rotation. theyre all in the middle. i was going to use something like this: tp @a[distance=8..9] ^ ^ ^-.2 
but, this doesnt work because all 36 of them will trigger this command when a player tries to exit the area. is there a way to only target players that the armor stand is facing with a 10 degree margin? or use ^ in target selectors?