Grinding Gears & Pressure Issues

Hi all,

I've been lurking for a while but can't find a post with my issues so wanted to see if the hivemind can help.

Recently my 2010 1.6tdci has been occasionally grinding in a pretty concerning way when going to change out of first, happens maybe every second or third drive when car is cold and seems to happen more when outside temp is cold (has been happening more lately but not sure if that's because of low temps or degrading components). When going to change clutch feels normal but there will be slightly more resistance than usual when moving stick out of first, if I move it anyway there will be loud grinding noise until its back in another gear despite clutch being fully in and even while stick passes through neutral. My current guess is slave cylinder or sticky clutch shaft but hoping its something easier to repair. Have bled clutch hydraulic fluid which didn't seem to make any difference.

I've also been getting codes P0234 and P2002 for overboost and dpf fault which cause engine light to come on. I've cleared codes for a while to see how long it takes them to come back. P0234 seems to trigger every few drives when under load e.g. overtaking on hill, P2002 seems more random. Car drives fine with engine light on but I'm unsure if damage is being done internally. Current plan is replacing dpf pressure sensor and possibly silicon tubes then trying to keep exhaust hot for 20 mins to clear out gunk on dpf and hopefully turbo vanes (does this need to be at consistent revs or is it fine to have it around 3000 occasionally dipping as may be hard to maintain a constant speed?). Has anyone had success with foam dpf cleaner sprayed in through sensor location or a fuel additive?

It would be great to hear from anyone who's dealt with similar issues or has ideas for more accurate diagnosis.