There's a guide for handling this, which notes that it is:
a) difficult to remove, and
b) an ML2032 (not CR2032), which is rechargeable. [guide|23376|Guide to Logitech K750 Keyboard Battery Replacement]
I would surmise that their tech support has had bad experiences with people replacing the battery with the non-rechargeable battery (which could, theoretically, explode, given that it's a lithium cell).
Dak