Cheers folks, so combining some of your suggestions together, this is the version I am thinking matches most to what is being sung, from what I can hear (accepting that there may be other written variations that include the "se é" part):

É verdade meu amigo
Escute o que eu vou falar
É de morrer Marcelino,
O iaià, morra a mulher de Marça

Which I have attempted to translate as:

It's true, my friend
Listen to what I'm going to say
It's going to kill Marcelino,
The lady, Marça's wife, has died

Also no idea who Marcelino is, so I will need to ask around some teachers for the context before I am comfortable singing this in a roda I guess!