Does misrepresentation by my sponsor affect my own admissibility as the sponsored person?

It can, because a sponsorship application is a joint undertaking involving both the sponsor and the sponsored person, and misrepresentation connected to the application isn't necessarily treated as belonging only to whoever actually made the false statement. If a sponsor misrepresents something material — about their own circumstances, the relationship, or another relevant fact — that can create problems for the sponsored person's admissibility, not just for the sponsor's role going forward.

This surprises sponsored applicants who reasonably feel they had no control over what their sponsor said or did. Immigration law nonetheless treats certain misrepresentations as capable of affecting the sponsored person because the sponsorship and the resulting application are so closely linked. The specific consequences depend on what exactly was misrepresented, by whom, and how central it was to the application's success.

Because this risk is often invisible to the sponsored person until something goes wrong, it's worth both sponsor and sponsored person reviewing the full application together before it's submitted, rather than each handling their own portion in isolation, and getting advice quickly if a concern about the sponsor's information comes to light at any point in the process.