Yes...you might be able to "tease" them out and re-plant.

Yes. 3 plants in the same spot won't thrive, But also, yes, you can pull out the others and re- plant them if you have space,

Yes. They also look like you may be over-watering them, that the one you keep needs to be fed, and it also needs to be staked or caged, supported in some way.

Dave

Or under-fertilizing them.

They look manganese-deficient, possibly lacking micro-nutrients??

Thank you ever so much to everyone for your help. This is my first post and I shall definitely be using this site more.

I currently live in Mozambique so things like fertiliser and tomato cages are simply not available. I will give them some cow manure though and try to fashion some kind of supports from tree branches. The fact I cannot find anything to buy sure does keep the cost of inputs down though!

If you plan on using cow manure, make sure it's composted manure, not fresh manure. Cow poo needs to sit for a year or so before applying to tomato plants. Otherwise you risk burning your plants.

Supports can easily be made with tree branches. Various forms of ridgid metal fencing can be used too.

And in practical terms, if you can pick up a piece of cow manure and crush it into dry stuff, its ready to use. And if you don't want to do that, its not ready. LOL!

I am sure people over there know all about how to use cow manure as manures are what is available as fertilizer.

But in my experience you can mix cow manure with garden soil ( 40/60) and top dress with it . stay away from the stem ( ~ 10 cm)

Seysonn

I run into a lot of people who don't know the difference between wet and dry manure as applied to plants.

We here, do. Many new gardeners don't. ;)