The "parallel entry" has me a bit tossed, but... If inbound 180 to the holding pattern you described, I'd make a direct entry so, when I see positive indication of station passage, I'd turn left onto 270 to join the outbound leg. This manoeuvre will produce a somewhat irregular looking track and may result in a slight overshoot of the inbound track, in the turn from the outbound to the inbound.
Pans Ops protection areas account for this, provided that you don't exceed applicable airspeed and bank angle limitations.
The chances are also pretty good that, if you'd gone right around the pattern once or twice, after completion of the sector entry, the plot of your track might still look a bit irregular. This can occur because of over-estimation, or under-estimation, of drift. The protection area makes an allowance for this because of the lack of track guidance on the outbound leg of the pattern.