Question about FT of PS 180 man $20 sit and go

[wpr101]

So I made it to the final table of the pokerstars 180 $20 sng with 21k in chips. There were two stacks there were noticably big around 50k; there were also two stacks around 6k. Others stacks varied in between that range. Blinds were at 800/1600 with antes. So my M is around 7ish.

I have 88 UTG I push and get called by AKs and lose on a QQ99 board. I was hoping someone with overcards called or I stole the blinds. Is this move +EV you think? It was one of the first hands of the FT so table dynamics were not established however it was probably pretty tight from what I saw.

Would a more standard raise of say 4000 be more appropriate and they lay down to an all-in? If I had less than 18k in chips I think it would be a clear push but at 21k I'm not sure.