I hate asking for mechanical advice online but could use some insight on the issues I'm having.

As of last night my 2013 started giving me issues, started having some really bad shuddering/vibrations coming from the clutch pedal when engaged, but also idles rough when the clutch is engaged and in first gear at a stop. Car idles fine in neutral or without the clutch pedal engaged in general. Never had clutch issues in the last 15 years I've been driving, google searches lead to potential clutch failure, but that's like trusting WebMD for any medical advice.

Using this opportunity to swap out the CMC for one with no CDV, but if anyone else has any experience like what I'm dealing with it would be helpful. Thanks

 

I can't say for sure, but my clutch felt much better after I bled the system. There was a lot of gunk that I suspect was blocking up my CDV. Maybe start there.

Seb makes a nice kit:
https://www.fitfreak.net/forums/2nd-generation-ge8-specific-sale-wtb-used-parts-sub-forum/106462-seb-s-garage-ge8-clutch-delay-valve-delete-kit.html

 

I did look at the reservoir and the fluids did look dirty. I’m going with a 01-05 Civic CMC to keep this budget friendly in the event it is in fact the clutch and/or flywheel. Certainly do wish I could afford the Seb’s kit. If that doesn’t work, I’ll try swapping out the slave cylinder before having to dish out the money for a clutch job

 

The clutch fluid needs to be changed, flushed, and bled just like the brake system. Might as well start there if you've never done it.

 

sounds like you might have some hotspots on your flywheel, if the symptoms are only while engaging the clutch.