How does margin interest deducted in Qtip trust?

I have a Qtip trust. In 2024, the trust had both short term and long term capital gains. It also had margin interest. I believe that the margin interest can be deducted against short term capital gains. However, my tax accountant use the margin interest to offset some short term and some long term capital gain according to the ratio of the short term to long term gain. For example, if the short term gain was $5000 and long term gain $10,000, margin interest $3000. My accountant used $1000 to offset the short term gain and used $2000 to offset long term gain. So the total income will be $4000 short capital gains and $8000 long term capital gain. Is my accountant correct?

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