Wrap spread looks like 3 points until I actually amortize both notes

The mismatch is doing you a favor on the balance sheet and hurting you on cash flow, and which one matters depends on whether you need the 378 or you're happy to accumulate equity.

Run it out. On your numbers the senior is retiring principal at roughly 720 a month early on and climbing steeply, because 22 years left at 3.9 is well into the amortization curve. The wrap at 7.25 over 30 is retiring maybe 205 a month at the start. So you're building around 515 a month of position in addition to the 378 of spread. That's the real yield, and it's why the headline 3.35 point spread understates the return while overstating the cash.

The default scenario you raise is the one to plan for, and your framing is right that you'd be foreclosing on a note whose collateral now carries a smaller senior lien than it did at origination. That's not a bad place to be, assuming the wrap is properly secured and recorded and your state's foreclosure process is one you can actually run at a cost you've priced. Judicial states will take longer and cost more, and that varies enough that you want a number from a local attorney before you sign, not after.

Matching the wrap term to the remaining 22 years is uncommon because it pushes the buyer's payment up hard, roughly 1,935 instead of 1,808 on 265k, and buyers doing a wrap are usually payment-sensitive. The more common answer is a 30 year amortization with a balloon somewhere in years five to seven, which caps your exposure to the underlying and forces the refinance conversation.

One thing your model is holding still that won't: the escrow on the senior loan. Tax reassessment after a sale can move that payment several hundred dollars, and it eats the 378 first.

The reassessment point is the one that would get me. In my county a sale resets the assessed value to the price and the tax bill can jump 40 percent the following year. At 378 of spread that's most of it gone, and the buyer's note is fixed.