The confusion has to do with 2 different provisions in the law. First, you have 401(a)(31)(B) which requires that "mandatory distributions" be rolled over to an IRA if the participant makes no election and the amount exceeds $1,000. IRS Notice 2005-5 provides that for this purpose, a "mandatory distribution" is one that is forced out under the cash-out rules and made prior to the later of age 62 or NRA (Q&A 2 is below). This is what's reflected in the 402(f) notice.
You then have Regulation 1.411(a)-11 which provides that participant consent is required where a distribution is "immediately distributable," which is prior to later of NRA or age 62. Relevant portion of the regulation is below. The $5K cash-out provision is an exception to this rule.
So, mesh those together and what you end up with is that after NRA/age 62, you can force out a distribution regardless of the amount. But there is no requirement to rollover the amount to an IRA if a participant makes no election. That means it's up to the plan terms (or arguably plan procedures) on what happens if no election is made - this is no different than with respect to amounts below $1K where the auto rollover isn't mandatory, but many plans do the rollover because it avoids uncashed checks. So, you first see if the plan forces cash-outs at NRA/age 62, and if so, and no participant election is made, does the plan or plan procedures provide for automatic rollover into an IRA or does the plan cut a check and hope it gets cashed.
From Notice 2005-05.
Q-2. What is a mandatory distribution?
A-2. A mandatory distribution is a distribution that is made without the participant’s consent and that is made to a participant before the participant attains the later of age 62 or normal retirement age. A distribution to a surviving spouse or alternate payee is not a mandatory distribution for purposes of the automatic rollover requirements of § 401(a)(31)(B). Although § 411(a)(11) generally prohibits mandatory distributions of accrued benefits attributable to employer contributions with a present value exceeding $5,000, the automatic rollover provisions of § 401(a)(31)(B) apply without regard to the amount of the distribution as long as the amount exceeds $1,000.
From 1.411(a)-11:
(4) Immediately distributable. Participant consent is required for any distribution while it is immediately distributable, i.e., prior to the later of the time a participant has attained normal retirement age (as defined in section 411(a)(8)) or age 62. Once a distribution is no longer immediately distributable, a plan may distribute the benefit in the form of a QJSA in the case of a benefit subject to section 417 or in the normal form in other cases without consent.