Which form does my partner fill in to bring dependent children in the UK?

I don't think anyone is disagreeing with your statement that he has no interest. They are just raising a potential issue that your partner may face based on others experience with UKVI.

Other people have run into this issue before and had visa applications turned down as UKVI make assumptions that are not true and if you do not plan the evidence in the supporting documents to get round that then she may have problems. Im awaiting the outcome of a visa application and the two stepchildren are my biggest concern even though have submitted fathers death certificate amongst the evidence. The system is uncaring and may have to be fought. Do not assume that they will believe you, seek additional information if unsure or give you the benefit of the doubt. Work on the assumption they will misinterpret, make incorrect assumptions and assume things that may not be true. An example is that unless there is evidence to the contrary they will assume that the father looks after the children and there is no need to issue a visa.

As I said to another poster the ideal scenario for children is no father on birth certificate or that father is dead and you have a copy of the death certificate. It is a harsh but true statement that I think other posters would agree with. If he is not on the birth certificate then make sure there is no mention of him in supporting documents or evidence that he has had any involvement in children's life. Make sure supporting documentation shows that your partner has had full responsibility for all the important decisions in their life and paid all the bills e.g. schooling, medical

Your partner may have an advantage over most people on here as a tier 2 visa holder so may have a easier ride than most. That said do not assume it unless you like wasting money and time on visa applications

Searching around found the links below

https://www.gov.uk/government/publi...ependants-of-uk-visa-applicants-tiers-1-2-4-5

Reading the guidance think the children will fall under this.

If you are outside the United Kingdom and wish to apply for leave, the majority of applicants must use the correct form available at: https://www.visa4uk.fco.gov.uk/home/welcome.

Not an expert on schooling but think that up to 18 and normal school age they are covered under general schooling for residents of uk. Post 18 schooling I think the link below may be useful. My reading of it is that unlikely to be much support post 18 but that was based on quick scan. Youngest if here until 18 may have more opportunities.

https://www.ukcisa.org.uk/Information--Advice/Fees-and-Money/Government-Student-Support

Excellent post and very informative .

Obviously you will appreciate that I have to be careful what I share on social media - thank you all for your input.