At most, I think SeaWorld can only be stabilized under its current financial situation.
The declines in attendance have affected all of their parks except SeaWorld San Antonio. That's a real problem given that their debt load is too high for them to really be able to compete in the Florida and California markets under their own finances. They've done a good job at investing in the parks with the budgets that they have..., but you'll have a new Universal park in Orlando soon, and you have massive Disney upgrades coming across the board. California is as competitive as ever between DL, USH, Six Flags, Knott's...
A regional group of parks that earns $60 per customer is where SeaWorld is, but that's not really going to work if they have to invest heavily in the parks at the same time.
They really need to consider a sale to a cash-rich corporate owner, or a restructuring like Six Flags went through around 2008 when they cut their debt load significantly from $2.8 billion to around $1 billion, which has allowed Six Flags to reinvest in their business and thrive over the past decade.
If SeaWorld was able to cut their debt load from $1.6 billion down to $600 million, they'd be able to reinvest over the long-term, especially as interest rates rise in the US. It's either that or a sale to a cash-rich corporate owner.