Transfer of funds from deceased spouse RRIF to surviving spouse RRIF. Taxable?

My grandpa passed away early in '25 and beneficiary of all his financial accounts was my grandma.

He had a work pension RRIF and a branch bank RRIF.

She went into their bank and had my grandpa's work pension company determine the amount of death benefit amount my grandma was entitled to and then did a direct transfer into her RRIF. However they liquidated the proceeds first and it was a cheque from the work pension that went to my grandma's account.

She also did a direct transfer of his bank RRIF into her bank RRIF (same bank as my grandpa).

T4RIF slips were issued for each transfer transaction.

She was surprised that the proceeds of both transferred amounts were in box 24 as taxable income.

I thought if a spouse dies, any registered accounts amounts can pass to the surviving spouse and remain tax-free (except for the amounts that are withdrawn)?

TIA