The online request form for the 60-day satisfaction guarantee is here.
https://ttlc.intuit.com/community/tax-topics/help/how-do-i-request-a-refund-for-my-turbotax-product/...
Did you apply online or just ask over the phone? The operator may have been confused about whether you were using the Desktop software or the online product, which have different refund policies.
Apple is very aggressive about deprecating old operating systems and removing support for them from the software developer's kit, so the only way to write a program that supports an OS version that Apple no longer supports is to use an outdated SDK. On the other hand, your Mac must be around 10 years old if it can't be upgraded and that's a pretty long life for a personal computer.
