Interesting question. I have not seen flare KO pot reprocessing on the DCU before. Seems reasonable but yes, I would expect fouling to be concern. Many units used to reprocess their slops (BD mainly) directly in the fractionator but stopped due to fouling issues.
Flare releases are heavily scrutinized in some places like california. So great care is taken to understand all the sources. Downstream of the PSV or other sources, you can put sensitive TI/PI to indicate if someone is “in” the flare. Also, PSVs will start to leak at 90% of their setpoint so find all the equipment and processes who are near this limit.