Go into MMB and see if 'Add OnBusiness' option is highlighted. If it isnt, then your company has an OB account and there is nothing you can do. If it is, then your company is not using OB. You can therefore open an account for your own imaginary business and then add the number to your future bookings through MMB.
Best use of 75k is probably World Traveller Plus to the US, Caribbean, Mexico, Africa etc - although you are far, far better off waiting until you have 100k and then redeeming for a Club ticket on the same routes, given that the difference between WT+ and Club is so massive.