Hello all premier pro gurus here, kindly help me this little things

hello all premier pro gurus. just watch this video. there i musked and track a object that i want to hide with an specific image, [not blur] how can i replace this musked area with image?. i means i want to replace that black tarcked area with image who will also move where i tracked[ see the video]


i can not able to find a specific tutorial regarding this issue.

kindly help me if you can, much appreciate