The value in Membership Rewards is achieved by transferring to an airline frequent flyer program and redeeming for otherwise expensive tickets. Expensive means longhaul (intercontinental) business or first class -or- domestic USA routes with a dominant carrier (no price competition). Any other use of MR points will generate no more than $0.01 each.

However, in your case the decision seems easy:

What type of award flight do you plan to redeem? $30,000 of general spending on Chase BA VISA will generate only 37,500 miles. You'll need at least 50,000 miles to claim a pair of economy awards, or at least 100,000 to claim a pair of Club (business) awards. How do you plan to generate those additional miles? You could put additional spending on the Chase VISA or you could pay $75 and pickup 15-30,0000 from your corporate card spending to unlock the value of the companion certificate.