I don't believe this IS verse line-numbered material. It's more like a play...consider it prose. And yes, then you would insert three blank spaces at the beginning of a braille line...and number every line (as it is prose). The first bit is the introductory paragraph, then your dialog would be 1-3. The italicized parts that start with Marta appear to be stage directions to me (blocked in 7).
Cindi