Does altimeter setting affect the vertical guidance in a LPV approach?
Short Answer:

No, the vertical component of LPV approach performance is based on WAAS GPS input, not the altimeter or barometric system.

Longer Answer:

Your assumption about LPV performance is correct: Baro-VNAV is not used for LPV approaches.

On any type of approach with a Decision Altitude (DA), the aircraft's arrival at the DA is determined by the pilot's reading of the aircraft's sensitive altimeter.

If the altimeter is set to an altimeter setting report from a distant reporting station, SFO in this case, then the DA may be increased to give additional altitude margin to allow for variance in local atmospheric pressure.

This is true for the DA or Minimum Descent Altitude (MDA) on any approach, whether a GPS approach or not. See the MKT ILS 33 and MKT RNAV 15 for other examples of this. See the following excerpts from the Aeronautical Information Manual on altimeter settings for approaches (emphasis mine):


  5-4-5
  a.
  4. Approach minimums are based on the local
  altimeter setting for that airport, unless annotated
  otherwise; e.g., Oklahoma City/Will Rogers World
  approaches are based on having a Will Rogers World
  altimeter setting. When a different altimeter source is
  required, or more than one source is authorized, it will
  be annotated on the approach chart; e.g., use Sidney
  altimeter setting, if not received, use Scottsbluff
  altimeter setting. Approach minimums may be raised
  when a nonlocal altimeter source is authorized. When
  more than one altimeter source is authorized, and the
  minima are different, they will be shown by separate
  lines in the approach minima box or a note; e.g., use
  Manhattan altimeter setting; when not available use
  Salina altimeter setting and increase all MDAs
  40 feet. When the altimeter must be obtained from a
  source other than air traffic a note will indicate the
  source; e.g., Obtain local altimeter setting on CTAF.
  When the altimeter setting(s) on which the approach
  is based is not available, the approach is not
  authorized. Baro−VNAV must be flown using the
  local altimeter setting only. Where no local altimeter
  is available, the LNAV/VNAV line will still be
  published for use by WAAS receivers with a note that
  Baro−VNAV is not authorized. When a local and at
  least one other altimeter setting source is authorized
  and the local altimeter is not available Baro−VNAV
  is not authorized; however, the LNAV/VNAV
  minima can still be used by WAAS receivers using the
  alternate altimeter setting source.


Note that Baro-VNAV is a type of VNAV system which uses barometric
altimetry as a basis for vertical navigation performance. An LNAV/VNAV approach can be flown using WAAS equipment without a Baro-VNAV system.