Is it unsafe to watch *unbooked* additional dogs?

Hello, all. So I'm another newbie to Rover here. I'm still "perfecting" my profile, figuring out a good main structure, getting a feel for how everything works & whatnot. My question right now is in regards to house sitting, the additional charges of watching multiple animals and how that works with the Rover Guarantee (which I do understand for the most part). Because before I made my account, I did a little bit of searching on YouTube to hear people's personal experiences of working with Rover, and I came across a comment one woman made about how she had a client book with her for house sitting. Apparently the client only booked for one dog, yet she actually had two that the woman was to watch (aka the client was dishonest?). The woman still did the sitting anyway, but also noted in her comment to other sitters that it could be dangerous (in the rare case of any emergency/injury, etc. with that particular unbooked animal) to not have that clarification in the booking of how many animals that will need to be looked after, because those additional animals could not be potentially "backed/covered" if an accident happens under the sitter's care. (And I'm also aware that Rover has its limits in what it'll help with)

Is this true or a misunderstanding? I just want to clear this up so that in case it is actually that important, I will be sure to note this in my profile for potential clients. Thank you in advance!