So let's see... they couldn't find a link between red meat and those diseases, but did find a link between "processed" meat.
Here's what we know then:
1) Red meat doesn't cause measurable damage.
2) Processed meat and those diseases are correlated.
3) The article admits that we don't know the mechanisms of action, or even if the relationship is causal.
So let's apply Occam's razor which states that among competing theories, the simplest one is probably the correct choice (I'm paraphrasing).
So which one is simpler:
1) Processed meats contain subtle compounds that cause these diseases, but these causes have eluded modern science despite our advanced knowledge of organic chemistry, biochemistry and genomics. These causes have also eluded our detection despite access to complex diagnostic assays, sophisticated imaging and the vast availability of laboratory animal models.
Or...
2) Someone willing to eat spam and deviled ham in a can don't give a shit about exercise, smoking, obesity and substance abuse either -- so they get these other diseases more often too.
I'm gonna go with (2) Regis. Final answer.