for ID to be considered science, the definition of scientific theory had to be changed
Yes it must be changed so that material causes are not the only ones allowed to be considered.If 'matter is all there is' that would be fine, but we don't know that for a fact and some things are better explained by non-material causes. In other words if purely natural mechanisms produced life on this planet then great but if there's evidence to say that that may not be so, then limiting what is allowed to be defined as science to natural causes may shut out the real cause -thus the truth of what actually happened to produce life on the planet may be excluded by what is currently accepted as the definition of science.
As an analogy, imagine you have to hypothesize on how computers came to exist but you are not allowed to mention man -you are limited to only those processes that occur within a computer -the correct answer is thus excluded a priori.
Id proposes that natural causes may not be the only explanation possible for life on this earth but it does not attempt to get into who or what the creative intelligence may be because the identity of the designer is not part of science -that would be part of a theological debate.The point is not to exclude the potentially correct answer by limiting the definition of science to material causes and passing it off as fact since it may shut out investigation into the truth of what actually did produce life.
Much like the identity of the creator being out of the domain of science, so would things like voodoo and charms be out of the realm of scientific investigation.