Safety of (re)cooking potentially raw beef from delivery
It is common, when preparing pho, to add raw, thinly sliced beef to the piping hot broth.  That way the broth essentially cooks the beef.  So what you received is not surprising.  It is impossible to know, from what you have written, if there are safety concerns.  IF the beef was handled correctly at the restaurant, and IF you received and cooked the beef within 2 hours of it being in the "danger zone" (if it was in the danger zone...impossible to know without understanding how it was transported), then there is not a safety concern.