Where in her colon is the suspicious polyp, and what is the planned surgery? Are they planning some sort of colectomy? I'm assuming that a "clear" CT in this situation means no wall thickening, no enlarged lymph nodes, and no visible mets? Did they do a full set of scans: thoracic, abdominal, and pelvic?I guess that sometimes they plan some type of colectomy based on the state of a polyp, without obvious signs of cancer on CT. (Maybe that's how people end up diagnosed as stage 1!
Try to get access to her pathology reports, and make sure they do basic genetic testing on her tumor, if there is one: MSS/MSI, KRAS and BRAF wild-type or mutated. Every medical entity I've dealt with here in the US has a patient portal, where I can read test results, surgery reports, etc. If not, she should call and ask her doctor for a hard copy of her reports.
BTW, is the doctor she's been talking to a gastroenterologist or a colorectal surgeon?