First you need to make sure that your installation of Amesim does contain the submodel c codes.
For example I think this is not the case with student edition.
A quick way to check is to navigate to Amesim installation folder and find the folder libmec/submodels.
If you see c codes there you're good, there will be a LML034.c which show you the actual code (which is what's in the Help file).
If you have these codes, you can also start Ameset and open the submodel you're interested in, save it as a new submodel and edit its code.
I hope this helps.
I'm afraid if the c code is not available in your installation Ameset will only generate an 'empty shell' code without the actual equations.
That generated code will actually reuse the existing structure/specification of the submodel you've opened (which is defined in *.spe file - always available in that submodel folder). For the lever case, the output velocities formulations are actually defined in those *.spe files, that's why you see them. But alpha is computed explicitely in the code...
Even if the code is not available, the help file usually gives the details of the calculation or references.
The case you mention (mobility bn) is special, we only give references as there are some ip restrictions here. Meaning that even with the c code you wouldn't see the actual calculations which are done by a library function which code is not open...