What can I use to clean sofa cushion?

[Gasbox]

The dog has vomited on one of the sofa cushions, I've scrubbed it but it still stinks. I have a Bissell spot cleaner but no cleaning solution and can't get to the shops today, any thoughts what else I can use in (or before using) the machine? I have bicarb, white vinegar, soda crystals and all the usual general cleaning and laundry stuff in the cupboard but the internet isn't being much help as using anything other than the branded solution isn't recommended but I really need to do something with it today. The cushion is currently damp so sprinkling dry bicarb and vacuuming isn't an option and I feel like it needs cleaning properly first anyway so I'm after 'wet' options for now if anyone has any ideas?

Remove the cover put on a cool wash in the machine. The filling should just be a wedge of foam so rinse it in your shower and leave somewhere to dry thoroughly.

What fabric is it?

It depends if you can remove the cover from your cushion.
If not and it's made of easily squeezable foam, I would put it in a large tub of water and squish it really well for a while, in warm water that perhaps has vinegar in it to help deodorize.
Put the cushion in your spinner if you have one hopefully you do, spin it as well as you can and hang it to dry, preferably outside.
Surface cleaning the cover just won't do it alone.
The vomit has most likely seeped into the filling.
It's hard to give advice when you can't see or feel the cushion and its cover.

Biological washing powder or liquid, weak solution in warm water. Sponge it on and blot with a towel. Repeat as many times as you can stand to do it. After the final blot sprinkle bicarb over it, doesn't matter if it's still damp, when dry hoover the bicarb up.

Thanks all, had to do a bit of an emergency dash to PIL's in the end so haven't got far with it, picked some detergent up while we were out so DH has just done it with the spot cleaner and we'll see where we're at when it's dry. Suspect it is going to need more than a surface wash though yes, Ddog is elderly and poorly so it smells particularly bad, honestly think we may be losing him in the next few days tbh