Please be informed that SARFAESI Act by and large override other laws in force
Moreover the provisions of SARFAESI Act or the rules made there under shall be in addition to, and not in derogation of, the Companies Act, 1956 (1 of 1956), the Securities Contracts (Regulation) Act, 1956 (42 of 1956), the Securities and Exchange Board of India Act, 1992 (15 of 1992), the Recovery of Debts Due to Banks and Financial Institutions Act, 1993 (51 of 1993) or any other law for the time being in force.
In your case, the provisions of SARFAESI act will apply irrespective of Sec 185 and 186 of Companies Act 2013 (amendment dated 12 Sep 2013.)
Also i presume you have filed your grievance if any under Sec 17 of SARFAESI Act, Even a guarantor should have appealed under Sec 17.
The borrower company assets should be auctioned first.
Since the guarantor is a limited company in the event of the short fall AFTER sale of assets of Borrower company, then the guarantor company should be provided enough opportunities for guarantor company to repay the loan and assets can be put in to auction (subject to there being no charge / claims from the bankers of the guarantor company ).
In the event of the guarantor company having a charge/claim on its assets on account of its own borrowings from their banker's, the banker's liability should be settled first ahead of the liability arising out of guarantee.
Hope this helps.