I see on second viewing that the "beaming the gene therapy" is a little less extreme; it's a topical salve rather than a remote injection.
They acknowledge in dialogue that Chapel's first injections didn't involve access to Kiley DNA. She just changed their appearance. Which doesn't explain the retinal scans.
They acknowledge in dialogue that Chapel's first injections didn't involve access to Kiley DNA. She just changed their appearance. Which doesn't explain the retinal scans.