The 38-year-old crashed to a six-over 77 on the opening day at The Grove and a one-under 70 in the second round proved little consolation.
"The crowds have been great, the course is in fantastic condition, you should have no excuse," Donald told reporters at the par-71 venue just outside London.
"The greens are absolutely perfect. Unfortunately I'll be watching over the weekend and not playing which is disappointing.
"I thought as host they might be able to give me another nine holes to see if I could make the cut," joked the Florida-based Englishman who spent 56 weeks at the top of the rankings in four spells in 2011 and 2012 but has since slipped to 69th.
Donald's first tournament appearance in four weeks ended with three birdies in five holes but it was too little too late.
"I was definitely very rusty yesterday," he said. "My short game let me down and I didn't hit enough greens.
"It wasn't the golf I was hoping for but it was nice to finish with a few birdies."
Donald, who took over as host from Ian Poulter, said it was good to get an insight into how things worked on the other side of the playing ropes.
"I saw a different side of what goes on to make tournaments run, to make them unique. It's been fun to be a part of," he added.
"It's tough to juggle both (but) I should have played better
than I did the last two days. I'll be sticking around, I'm very proud to be a part of this."
(Editing by Ed Osmond)
