They should have been there in their 1st season.
Expansion teams are never that successful that quickly. There's a reason that Perth and New Zealand dominated the league for a decade, and it wasn't that they constantly changed all their players and coaches. Stability and chemistry are important, not to mention that approximately 2/3rds of the players in the league were contracted in year one making them unavailable to SEM.
I don't recall an expansion team
ever making top three in their first two seasons, where the team was starting from scratch rather than importing a lower-division team as often happened in the 80s.