Are you sure that originating and receiving accounts are 401(k) accounts? I suspect not. A trustee-to-trustee transfer of an IRA to another IRA of the same type must not be reported. It is neither a distribution nor a rollover.
A 401(k) and an IRA are two different kinds of accounts. Any account from which you receive a Form 5498 is an IRA, not a 401(k).
With regard to a direct rollover from a 401(k), it's entirely untrue that the reporting of a direct rollover of a distribution from a 401(k) is discretionary. It is required to be reported. From the Instructions for Form 1099-R, page 3, Direct Rollovers: "You must report a direct rollover of an eligible rollover distribution." Since the plan refuses to issue the required reporting, I suggest contacting the IRS as described in Tax Topic 154: https://www.irs.gov/taxtopics/tc154
