I agree with buyer's counsel. Also, I agree on requiring a determination letter filing on the terminating plan. As buyer in a stock sale, it assumes all the obligations of the seller corporation. Presumably the plan is being terminated pre closing and the buyer is going to handle post-termination administration. Even if the DB plan was spun off and terminated, if there is an issue under that DB plan, there is a potential that liability could still fall back on the buyer if the IRS/PBGC thought that the spin off was a sone type of subterfuge to escape liability. Normally, in the case of a terminating DB plan, you would seek a letter and no distributions would occur until after the letter is received.
I also agree that a QRP cannot be used if the plan terms simply state "any excess should be allocated among participants" without anything else. You conveniently left out language in IRS 7.12.1.17.1.2 (11-10-2022) @sobrienTPS states that provision from the manual correctly "a plan could provide a direct transfer to a qualified plan or choose to allocate the excess assets to participants (as IRC 415 allows) in the event the reversion language is absent or not in existence long enough to allow a reversion." The conditions of if the reversion is not allowed or not in place for 5 years modifies the allocation of excess asset to participants... the conditions do not modify the use of a QRP. I have always read this language to mean you either can (1) use a QRP or (2) allocate if you can't use a QRP.
But youhave the perfect scenario to let the IRS decide. Amend the plan to permit the QRP, with the amendment laying out exactly how much of the excess assets will be transferred to the QRP, and how those amounts will be allocated in the QRP, CLEARLY indicating the effective date of the termination of the DB plan and the effective date of the change to the reversionary language. If the IRS blesses it, then all is well. If not, you are back where you are at now. If they don't permit the QRP, it should not be a problem because most plans would not permit distributions prior to the issuance of the IRS determination letter, and all that will be required is to work out is how to allocate the excess assets to the participants. If there is more than can be allocated, the IRS will be there to let you know what to do with the rest. Either way, as buyer's counsel, I would not be letting the seller walk off with any of the potential reversion. At most, we could escrow the amounts until resolved.
And, yes, we always amend a plan for the QRP provisions (usually these provisions will contain language that is also going to be used in the QRP plan document) along with always requiring a letter on the termination of the plan. You should tell the seller/buyer, you are a TPA... not a lawyer. They can ask you your thoughts but no matter what you say, it should always be followed up with... but you should really ask your lawyer.
As always, just my thoughts with absolutely no research...