I hope your husband is recovering well from his treatment to remove the tumor for biopsy. As there are different types of radioactive and nonradioactive dyes used for radiotherapy and because I am not medically trained, I can't provide a full answer on the scans requested by your husbands medical team. But I think has given the best advice: ask for clarification from your husband's healthcare team.
A member of our editorial team have written something that may be useful to you and your husband. We have an article about the different imaging tests that may be requested. You can read more here: https://bladdercancer.net/diagnosis/imaging-tests.
Wishing you the best for the scan and please keep us updated on how everything goes. Phil, Moderator,