What Causes A Swollen And Tender Area In The Anticubital?

My daughter recently had antibiotic therapy after serious mva..it was about a month ago..her left anticubital has a large swollen..red..hot to touch area..took to er lastnight bc appears to be getting worse and very painful for her. I am a rn myself so have seen thrombophlebitis but it appears much worse than I have seen. They did xray of elbow which showed slight soft tissue damage and blood work didn t show any kind of superinfection. She had a gm of rocephin and is taking keflex..asa and ibuprofen and applying heat.was told if not better in 48hours to come back in. There has been no improvement thus far..24hours and very swollen and painful..I am concerned that the longer we wait the worse the tissue damage might get and would like to avoid any type of surgical procedure bc she is currently undergoing reconstructive surgeries of face and eyelid..also .what r the chance of an embolism traveling to lungs etch from this Type of area such as the anticubital? Capillary refill is good and pulse good but very concerned bc symptoms of infection, pain and immobility. Please advise me on danger of waiting for additional intervention