Pesch & Plail's 2012 paper reports direct statements from Boltyanskii and Gamkrelidze to the authors, not only a reading of the written 1994 report

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Elsewhere in their 2012 paper, on a different point — whether the Pontryagin group knew the calculus-of-variations literature during the mid-1950s development of the maximum principle — Pesch & Plail write that "both Boltyanskii and Gamkrelidze concur in statements to the authors" that comparable calculus-of-variations conditions were not known to the group at the time, despite a 1950 Russian translation of Bliss's 1946 monograph existing. "Statements to the authors" establishes that Pesch & Plail had some direct contact — correspondence or conversation — with both men, beyond reading Boltyanskii's cited 1994 written report.

This sentence sits in the paper's section on the group's awareness of prior calculus-of-variations work, immediately before the section recounting the naming-pressure testimony, and it is not explicitly tied to that testimony. It cannot be read as direct confirmation that the naming-pressure account specifically was restated to the authors in person. What it does establish is that the vault's existing naming-pressure claim rests on historians who had an ongoing direct relationship with their subject — not solely a thirty-year-old written report read cold. That is a real, if partial, strengthening of confidence in the secondary account's fidelity, short of the primary confirmation the open question still asks for.