1. It's doubtful that any distribution was actually made. You should be able to determine that by logging into Fidelity and examining your account balances.
2. The amount of the failed rollover to the Roth IRA (the excess deferral and attributable gains) became a regular contribution to the Roth IRA and must be treated as such. If Fidelity has not already done so, you should probably ask them to reclassify this amount as a regular contribution. (Perhaps Fidelity did this in lieu of an auto-issued "distribution.") You'll then do whatever is appropriate with these funds as a regular contribution. (I'm guessing that if you are making after-tax contributions to the new employer's 401(k), your MAGI might be too high to be qualified to make a regular Roth IRA contribution and would need to obtain a return of the excess contribution or recharacterize it to be a traditional IRA contribution.)
Any gain attributable to the excess deferral to the Roth 401(k) will be taxable, but the excess deferral amount itself will not be.
Moving this year's funds to another Roth IRA would likely only complicate the calculation of attributable gains.
