Tier 4 Risky situation PLEASE HELP

Hello,
Because of the incredible delay caused by my student loan I have exactly one week left to apply for visa before my latest date of acceptance(11th Oct). I live in Oman where even a standard application gets a decision within 5 days. Since it is October now there shouldn't be a large influx of student visa applications as most people in September intake are probably already there. However, the complication is that in the past my father was refused visa for the UK that we couldn't afford to appeal, and so was I as his dependent (I was 15). This means that even if I use a priority service my application will possibly be delayed. The outcomes being:

1) I get my priority visa in 3 days and all is good
2) My visa is delayed, I get it after the 11th and the uni curtails it (they were very unwilling to give me an extension) which would be terrible for my immigration record

I could still defer but I really want to try and make it this year. Does anyone know of how long the delay caused would be even if I used the priority? Is it worth taking the risk?

Okay I personally think that it’s too much of a risk because my visa that was meant to take 15 days took 44 days eventually my Uni contacted them because the latest date of enrolment was approaching and that’s how it came back 2 days later. but even if your loan was delayed if you have your papers in order that are required such as the bank statements that are in line with the 28 days period and your financial sponsor letter and your CAS it won’t be delayed. Advice call your Uni to call UKVI to speed things up once you submit. Tier 4 is a points based system despite previous history. Usually if they delay your visa it’s because you have missing documents that’s why am emphasising on having your documents ready and in order.

Good luck!!