We replaced the oil in one of our compasses on an broom 37 that we had...at the time if I remember correctly we had to get the specific oil for the type of compass that we had, we went back to the manufacturer to get the oil who had different viscosities of oil for different models of compasses. Try going back to whoever made your compass and see if they can help.
I recently replaced some of the oil in my Bosun Grid Compass with Liquid Paraffin & it worked fine.
I posted the same question as you on this site & got lots of good advice. Try searching for the thread.
One thing I was told was to put the compass & the Oil in the freezer for a few hours before filling it. It helps to reduce the size of any bubble that remains.
Problem is the compass is a Danforth ,"freedom" type and I gather that Danforth has gone out of business!! So question still remains what type of fluid?