I am unsure about this subject because, in the first image, it does not seem a protoplanetary disk, but then in the final images seems to be a disc. So I guess it is a good candidate because it could be circular. What do you think?
In any frame; especially DSS2 and 2MASS that the object does not look round; the button for that should be highlighted. Even if it were round all the way through the plates; in this situation there are multiples inside the red circle. "If it has a tail its bound to fail." Multiples seen in 2 or more frames is instant rejection but describe all that you see and comment on it in talk. Welcome to the "disk side of Zooniverse"