The TSM is not a "sine qua non" requirement

The Board speaks to the TSM test in Ex part RADICH

As prescribed by the controlling case law, while it is often necessary
for an Examiner to identify a reason for combining the familiar elements obtained from the prior art in establishing a prima facie case of obviousness, the identification of such a reason is not a sine qua non requirement. So long as the Examiner provides an articulated reasoning with some rational underpinning to substantiate the obviousness rejection, such a conclusion is proper. (...) As noted above, the case law allows the Examiner to look to the state of the prior art, including the knowledge of the ordinarily skilled artisan to arrive at such a reason for combining the known elements of the prior art. Consequently, the Examiner’s reliance upon the cited references in order to arrive at an articulated reason with a rational underpinning to support the proffered combination is proper.

Yes, KSR is cited:

The U.S. Supreme Court has held that “[t]he combination of familiar elements according to known methods is likely to be obvious when it does no more than yield predictable results.” KSR Int'l Co. v. Teleflex, Inc., 550 U.S. 398, 416 (2007). The Court further instructs that:
[o]ften it will be necessary for a court to look to interrelated teachings of multiple patents; . . . and the background knowledge possessed by a person having ordinary skill in the art, all in order to determine whether there was an apparent reason for combining the known elements in a the fashion claimed by the patent at issue.
Id. at 418.