Summary
Yes - you can skip HMRC if other data sources (Banking and/or Payroll) are available to you in Konfir. However, if your verifier has only enabled HMRC as the data source, you will not be able to complete your verification through Konfir without connecting HMRC.
What to do
If HMRC is optional (other sources available):
If your verifier has made other data sources available for you, you can skip HMRC and continue with Banking and/or Payroll, then submit your verification.
Note: HMRC often gives the most complete UK employment history; skipping it may mean your verifier asks for extra documents after you submit.
If HMRC is required (no other sources available)
If your verifier has not made other data sources available for you, you won’t be able to use Konfir without connecting HMRC.
You'll need to contact your verifier directly to arrange a manual verification process that doesn’t use Konfir (e.g., document checks & referencing).