Child dependant visa refusal - reconciling with father

Good evening all,

I moved to the UK in Jan 2024 from Kenya, leaving my 4 year old daughter with my parents.

I recently got a refusal for her visa application on grounds that I have no sole responsibility (father gave consent saying he is intending to join us after his contract ends later in the year - he is working at a naval base outside Kenya. I gave bank statements, letters from schools, receipts/ bills, etc. to show am responsible for her upkeep and upbringing - didn't seem to matter). The letter also said I did not respond when requested additional information for serious and compelling reasons. I did respond, however, I realise now that the reason given (father is not in Kenya, phycological disturbance and grandparents being old to care for her) may not be compelling since the argument is I choose to seek employment and move to the UK.
The father and I were never married legally (traditional wedding was done in 2019) , in fact we have been separated for close to 3 years now and in reality am responsible for our daughter. In that period we have tried to get back together but it has been challenging. In October 2023 he moved for work overseas - we agreed to try work our differences and if successful he would join us.
We believed at the time it would not be this complicated for our daughter to join me first. In fact I got my mother visitors visa to bring her and help us get settled.
If all works out we shall marry (although now I realise that it can be seen as self serving only for purposes of obtaining visas - I had indicated unmarried partner in my application). We can attempt to prove that our relationship has been subsisting under unmarried partner but obviously there are gaps. I also have to be patient for him to return to Kenya and make necessary arrangements to be able to apply at the same time as our daughter. Unfortunately, my daughter continues to suffer the impact of my absence as she does not understand why I have been gone for so long - it is difficult.
If it does not work out (which is a likely possibility and the actual reason for posting this), what other options do I have that will allow me protect my daughter the most and have her join me as soon as possible?
(Apologies for the long post - had to paint the whole picture).

I will be waiting for your kind response, thank you.

Read below post from @vinny about sole responsibility

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