I take it you have your own reasons for applying electroless nickel as the barrier layer underlying the soft gold layer. Electroless nickel will work just fine for your application.
Having said that, if your wire bonding sights are bussed to allow for Gold plating, then they also are bussed for electrolytic nickel plating, which is gnerally a much less demanding process to run and maybe accomplished using the same racking just prior to gold plating.
Electroless nickel has traditionally been used where no bussing is available.
An excellent surface for gold wire bonding is electroless nickel/electroless palladium /flash gold at 100uins/12uins /1uins (nicroinch) respectively.
George Milad
HDI Consulting
Chairman IPC Plating Committee
(516) 901-3874 cell