Morgan was part of the Wales Under 20 fightback against England in the second half of their Six Nations opener on Saturday, when, despite trailing 26-13 at half-time, they scored the only points in the second half and lost 26-20 in a nail-biting finish.
Former Dragons and Newport scrum half Alex Walker remains with the Wales Sevens squad for Las Vegas after receiving a call-up from his new Sydney home in time for the Wellington Sevens after Nicky Griffiths returned home injured.
Wales play Kenya, Uruguay and New Zealand on Saturday on Day One of the USA tournament.
Wales Sevens squad for USA Sevens:
Lee Rees (Scarlets), Rhys Jones (Newport), Gareth Davies (Cardiff), Rhodri Gomer-Davies (Dragons), Ifan Evans (Llandovery), Rhys Shellard (Cardiff), Richie Pugh (Scarlets), Alex Cuthbert (Blues), Jevon Groves (capt, Dragons), Alex Walker (Eastwood, Sydney), Adam Thomas (Pontypridd), Matthew Morgan (Ospreys)