Can I finish my college degree program while being on TDIU?

Specific to your question, there is nothing that prohibits the use of Vocational Rehabilitation if you are TDIU and many do. However, TDIU and VR&E address different needs of a disabled veteran.

The VR&E program provides education and training assistance to veterans with service-connected disabilities who need help preparing for, finding, and keeping suitable employment. TDIU benefits compensate individuals who cannot work gainfully because of a service-related physical or mental disability or disabilities.

Theoretically, you could be rated as TDIU according to the VA and be approved for Voc Rehab by a VA counselor.

However, I would advise you to discuss the situation with a VSO and/or a VR&E counselor. The VA made some changes to the M28C references* (think of this as the VA VR&E bible) about six years ago regarding TDIU and VR&E.
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* https://www.knowva.ebenefits.va.gov/system/templates/selfservice/va_ssnew/help/customer/locale/en-US/portal/ [login to see] 01018/content/ [login to see] 43195/M28C-Table-of-Contents?query=M28