It's not "white color on white background", it's emptiness -- syntax error in content makes Reader to abort rendering (silently, because users are not be alarmed, no-no). Solution works to extent of file it was tested with (since you didn't provide any). And, like I said: what entries are allowed in inline image description, what values are they allowed to have, did you check the manual? SMask is definitely not allowed. Rather, it would be ignored, if it wasn't indirect object. I suspect same as above: "0 R" between BI and ID keywords, but maybe forbidden colorspace or compression, whatever. Arbitrarily deleting soft mask will probably result in change of appearance.
And it's definitely not Perl anymore :)