“Dear Investors, we gave you plenty of warnings that an investment in Monzo would be illiquid.”
I don’t know how many people are asking for exception permission, but it does appear that it’s a significant degree more than the handful of genuine emergencies that Monzo perhaps expected. That would be my guess for where the delay is - too many requests to deal with gracefully - and that people who did invest sensibly but have now found themselves in exceptional circumstances have been caught out as a result.
tl;dr, Monzo shares are illiquid, everyone was told they were illiquid, everyone was warned about the risks. No-one should be surprised that shares they were told were illiquid turn out to be illiquid.
(ETA: for the avoidance of doubt, I am not and have never been an employee. Views are my own.)