MAIN_SWITCH/STARTSAP_TRANS error validating the profile failed, see INSTANCE.OUT

We're currently trying to install Fiori on our EHP 8 system using SUM 2.0 but we are currently stuck at 70% in the phase MAIN_SWITCH/STARTSAP_TRANS with an error stating:

Last error code set:

System start failed

Earlier, validating the profile failed, see INSTANCE.OUT.

We're not able to go back past this phase to re-run it initially to correct any errors. We have adjusted our abap/buffersize parameter to 1GB but are still encountering issues. SAP has been working on this issue for over a month but we're not able to find a resolution. Would anyone have any suggestions?