Form 8275 notifies IRS that you did something wrong but there's a reason a penalty should not be assessed.  It should not be used as a square peg to pound into a round hole, even though IRS fails to provide round pegs.  @IRonMaN has the logical solution:  Just attach an explanation. If a CP-2000 is issued, just reply with a copy of the explanation, for the cost of a stamp and envelope.  

Attaching a statement is consistent with the IRS Schedule D instructions, on nominee distributions of capital gain distributions:

If you received capital gain distributions as a nominee (that is, they were paid to you but actually belong to someone else), report on Schedule D, line 13, only the amount that belongs to you. Attach a statement showing the full amount you received and the amount you received as a nominee. See the Instructions for Schedule B to learn about the requirement for you to file Forms 1099-DIV and 1096.

Technically, the personal representative is probably required to file a 1099-B showing the nominee distribution of the stock sales, but I doubt many people do that.