Already diagnosed w/StageIV IDC. Breast MRI suggests Inflamatory BC. Is that possible?

It is. Anything is possible, but a tissue diagnosis is needed, usually with a biopsy of some sort. If that shows an inflammatory cancer, then chemotherapy and RT is usually recommended first. The waiting is the hardest part, but your doctor has a methodical approach to get the answers. Take a deep breath, hang in there and good luck.