Multi-session was something created for CD and not DVD, although lots of software allows it anyway. When you burn a CD, you write the lead-in, the data, then the lead-out and TOC (table of contents). On a DVD, you write the lead-in/TOC, the data, then the lead-out. Notice the TOC is moved and merged, and is why it doesn't work well on DVD. Making a multi-sesson means you write a sesson and then leave the disc OPEN. On a DVD, it means also writing multiple lead-in/TOCs, not good. The CD just kept writing a new TOC and the spec is built so it will read the last known TOC on the disc. It is closed later, if at all, usually after writing more sessions.
Anyway, most ROM drives cannot read multi-session discs (usually just burners). DVD-Video requires a single DAO/TAO session, and it must be CLOSED with lead-out. So no DVD player will see a disc unless it is closed.