In the second and third of the senses listed, まつ can be written as 俟つ. It's rare, but not an error. Though, I don't know if you should have been quizzed on that unusual spelling variant. I think you must have specifically this variant instead of the usual 待つ added to your learning materials for it to appear.
Ahh, I see! Turns out I did add that spelling to an old schedule a while back without checking the kanji first. I thought it was getting pulled in from Words For Japanese Basics, which is why I was confused, but I apparently did have the rare spelling elsewhere and it came from that. Thank you both!