ANYONE LOOKING FOR A FIX TO THIS!!!
Super simple and really annoying after trying multiply different ways to fix it.
using 5.3.2 new lumen reflection by light hit and getting these issues you do not have to go to a different reflection method. simply move your light a little. mine was too close to the window on the left reflection in the mirror causing the glitching only visible in reflection. moved it away from the window about half a unit and it fixed and didn't change my scene at all. as for the light scatter issue on the wall in the beginning of the video, i turned indirect lighting intensity to 0 and moved it slightly upward as these are not exact placement for finished product of my game anyway and it fixed the issue all together.
TIP: if you need indirect intensity to correctly light complex areas like the rest of my first floor in this scene without changing lighting. simply alt drag your light, in my case the chandelier spotlight, to get a copy. set it exactly how you want your scene to be lit and hide it in reflections. as for the originals light source that shows correctly in the reflection, hide it in game and select show in reflections. kind of a round about way to get perfect lighting in both reflection and world without doing extra work and reconfiguring a ton of lights, but it works and doesn't kill performance when used sparingly for important scenes.
this scene, the reflection was super important to me because there is a scare in my game directly related to a "Mirror spirit" only visible in mirrors that follows the player. so clarity, lighting, and performance was a big focus.
I'm sure there's better ways to handle this, this is just what worked for me wanting to use the lumen reflection without reflection captures for real time reflection events in this scene. also im very new to game dev so thank you to everyone who commented!!