Affrication in /tʃ dʒ/ is "perceptually much shorter" than affrication in English /tʃ dʒ/, so we give alternate representations /ȶ ȡ/.
/u/ is "often articulated with the lower lip raised to form a slightly pouting posture with the upper lip, so that the inside of the lip is close to or touching the top teeth". In some dialects, it mutates preceding /t d/ to [tp db], [tf dv], [tsf dzv], or [pf bv]. So it's probably /ꭒ/, or more accurately an un-fricated /ʋ̩/.