I'd view a high cost of keeping Dotson in two ways: 1) Overall cost of hiring an O line, and 2) Stafford insurance.
What is Stafford worth? Is Stafford insurance worth paying a high premium?
Let's assume we jettison Allen and 'Boom, maybe keep Shelton (depending of plug-and-play center availability in the draft) and keep our cheaper but promising OL replacements.
My bottom line inclination is to free at least Allen and Boom's money, maybe Shelton's, and pay for the insurance policy premium, and get a right side run game (how many yards did Wiliams gain on the right side?) as a dividend.
Hoping for a separate but equal RG to show up - from somewhere - is a bigger gamble than hiring a new center in the draft and letting go of three vets who are less productive than Dotson.
At least that's how it seems to me - but I'll let Snead figure it out.