In fact, it went pretty well, though I only just managed to avoid destroying the music in its last few bars. I stopped counting my bars' rest and realised, as the music continued around me, that I would have to come in by guess-work. This was successful, but it spooked me and the demi-semiquaver passage looked alien on the page. I busked the penultimate bar, hoping that playing a repeated E-flat would fit. It did, we reached the last bar successfully and I returned to my seat, knowing that it had been a close call. The wine was welcome.
(In the YouTube video above, it is at 18:11 that I got into trouble. The bassoonist in the clip does it effortlessly, of course.)