Very few photos from last night's event have been shared online, and there were sadly no photos of Tom rehearsing posted anywhere. A cast photo was tweeted by Lucy Davis, but this didn't include Tom. Luckily a few photos have been uploaded to Instagram today, which Tom seems to be in. The above photo was shared here, and the others are embedded below.
I haven't been able to find out what play or character Tom was performing last night. Sorry. Those who wish to, can still donate via the Whither Would You Go website.