The address is incorrect: there's no Yarrunga St - but there is a Yarranga St; Illawarra Rd should be Illawarra Hwy (A48, aka Hoddle St). The exchange isn't at the corner of Yarranga St and Illawarra Hwy, it's at the rear of 63 Hoddle St (the block at the SW corner of the two thoroughfares; i.e. it's on the western side of Yarranga St about 50 m south of Illawarra Hwy. Anyone looking for it at the corner won't find it; besides, there's dense tree cover where it is, so it's not easy to spot.
150°35'37"E, 34°35'21"S point to the centre of the block 63 Hoddle St - but the exchange is at the rear of the block. The decimal form 150.59362, -34.58941 points to the actual location of the exchange.