OK I stand slightly corrected on the P2/Co-Pilot bit, but of course it could have been logged as such under para 3d of page 44 with prior arrangement.
Apart from that, it would appear that Dent can only log the time as SNY which counts as zilch. SNY time is surely reserved for someone without the appropriate licence, but as Dent has a Fzn ATPL he should be able to upgrade his role a little.