Quick Question About Hakone Freepass

Hi everyone, I’m planning a trip to Japan in November. We are tentatively thinking to stop by Hakone on our way back from Hiroshima (so it’ll be Hiroshima > Hakone > Tokyo). I know we would only use the shinkansen up until Odawara and then transfer. My question is, would the roundtrip from Shinjuku freepass be valid if we don’t start in Shinjuku? I would just use it for around the Hakone area and then to take the Romancecar back from Hakone > Tokyo. It’s cheaper than the Odawara-only one and buying a separate Romancecar ticket. We are not getting the JR pass (not worth it money-wise). I would assume it is but knowing Japan being so strict about rules I wasn’t sure. Thanks!