Bad experience

I went to McDonald Columbine Square on the 13th October 2023 to enquire for a birthday party of my 9 year son the lady by the name of Rose explained to me that I need to pay R300 to book. She further showed me menus/packages I can choose from & mentioned that the limited number is 10 kids over and above that e.g from 11 upwards is R100 per child however she never explain anything about refund , on the 16th October 2023 I realized that I now have 19 kids including their parents. I then went to request for the refund as the number has increased & I wouldn't afford to pay extra and the food will be too expensive for me too. Rose was off duty, the Manager on duty was called & I was told she's busy on the phone trying to arrange some training I must wait, I patiently waited until she came, she then told me that there's no refund as per the policy I told her no one told me about this before I made the payment, she told me it's beyond their control there's nothing they can do, she further told me that she's currently busy so she can't talk long with me and told me that the guy by the name of Trueman will talk to me. He tried to convince me to postpone the event to a later date before end of this year as it's impossible to get a refund more especially because I used my bank card not cash. He said he can make a plan for me that he can arrange that I don't pay for additional 9 kids & only pay for their food, I explained that the space is too small as the store is not as big as other McDonald's he said I shouldn't worry he'll make a plan. I told him that I've already made other arrangements however he was insisting that I postpone. I then left as my son was too hungry as I had just fetched him from school around 17h00. On the 18/10/2023 I went back to request for a refund unfortunately I was told the Manager I was engaging with on the 26/10/2023 is off and I must come back on the 19/10/2023 however I find this frustrating as I wasn't made aware of terms and conditions which I did tell Trueman the same thing. How impossible can it be to resolve this issue? I didn't receive anything in print nor being informed verbally about this and if I can't be reimbursed it means I'm like giving a donation to McDonald's without being informed ahead before and I there are many ways to sort out this matter. I'm highly disappointed especially because I am a regular customer at McDonald Columbine Square and the manager was not a friendly person to talk to, she's loud & even mentioned that Rose will go for a hearing & all customers were listening as she was too loud and I'm personally a soft person, I found this is so unprofessional to say in front of customers about internal issues or any internal discipline measures.