If you are turned down,then surely the status quo remains i.e if you are solvent and meeting repayments as they fall due, then surely there would be no court proceedings.
However if you are unable to meet repayments on the full mortgage, then you are insolvent and should get legal advice. The fact you applied for a split mortgage might not mean anything to the lender as they might not see a split as a viable option for you in the long term.
Again, get independent advice. Even go see a p.i.p if you think a Personal Insolvency case might be for you. There is the option of a 'Split' under a PIA and the p.i.p might be able to negotiate one for you, as opposed to the less favourable option of bankruptcy for the bank. The 'split' option in a PIA actually sees the warehoused amount written off in the 6/7 year lifetime, as opposed to maybe never having the warehoused amount written off in a regular 'split' negotiated between you and the bank.