Welcome, and thank you for the detailed MWE! I can confirm that I see the same behavior. What julia verison are you on (versioninfo())? Which versions of DiffEqBase and ForwardDiff are installed (]st)?
This probably has to do with the use of Requires.jl in DiffEqBase, since that struct is requiring ForwardDiff. I had hoped simply swapping the using statements would have worked, but seems like this isn’t the case. Probably best to open an issue at DiffEqBase.