Help me solve my puzzle

So i'm new to cryptography and i'm trying to figure out this puzzle/cryptogram for a competition to figure out the new name of a company that he's decoded in a puzzle.

He started out with a system of equations:
81ß - 41δ+34µ+64φ+0Ω-801=0
41ß - 41δ+56µ+44φ+0Ω-3=0
25ß - 33δ+35µ+54φ+0Ω-68=0
63ß - 24δ+30µ+51φ+0Ω-6000=0
And using a matrix i figured out that
ß=68
δ=553
µ=231
φ=153
Ω=any number (Omega has to have some special significance since it has no effect on the answers mathematically since it has coefficient 0)

Now i'm supposed to find a key with these numbers and use that key to decipher the new name.
It's a software company so i'm guessing some sort of binary cipher.
Any help would be greatly appreciated and sorry if I sound too noob for you guys i'm just starting to learn this stuff and figured you could help!

Without the encrypted text it's hard to say anything.

Thing that sticks out at me, though, is why Greek letters? Latin letters could've been used much more easily