Porsch is listed in Krätschmer as Untersturmführer and Fhr. of the SS-Panzerjagdkompanie Dora II – commando unit of the SS-Bewährungsverband 500 (AKA SS-Sturmbataillon 500), though he's listed as a non-KC holder in the updates at the end of the book.

Horst Wilke (SS-Art.Rgt.32) gives the following account of the battles in Halbe pocket in Krätschmer (in the Untersturmführer Friederich Blond's chapter):
(28 April 1945) ».. two Untersturmführers were decorated with KCs, for their actions… One of them was congratulated by Brigadeführer Wagner. He was a leader of an alarm unit from SS-Ausb.-u. Ers.-Btl.1, Untersturmführer Friedel Blond… On 18 April 1945 a leader of a Panzerjagdkommandos, a young Untersturmführer, which led a unit z.b.V. (special purpose unit) which mission was to destroy broken through enemy tanks, reported to the I./SS Pz.Gren.Rgt. 86. The comrades were equipped with panzerfausts and bicycles. When Russian tank spearheads pushed into the area northwest of Spreenhagen, the Untersturmführer's Panzerjagdgruppe was constantly engaged in our sector around Senzig, east of Königs Wusterhausen, Bestensee, Dahmekanal, Prieros and Streganzermühle. They were always »hunting« for Russian tanks, and in case of an emergency, also engaging broken through enemy infantry. We were very, very happy to have had this unit fighting in our proximity and was occasionally also used as battalion's fire-brigade. The mentioned Untersturmführer was originally from Totenkopf Division came and was one damn stubborn dog (ein verdammt sturer hund) which nothing at all could bring to peace. Probably on 28 April I observed the Panzerknackers above the Dahmebrücke, west of Streganzermühle, in action, as they hunted and destroyed broken through T34s and a little later west of Hermsdorf. This special unit was active again on 29 April in the Halbe pocket and was securing the withdrawals west of Dahme against tank icursions, while the I./86 was preparing itself as a break-through unit. If I remember correctly this Panzerjagd unit destroyed 27 Soviet tanks in our area in the period from 18 till 28 April. The young leader of this unit was one of the two Untersturmführers, to whom Obergrupenführer Kleinheisterkamp gave the KCs on 28 April 1945. Its name was probably or similar to Porsch.«

Horst Wilke's accounts are also in Tieke's book Das Ende zwischen Oder und Elbe, but interestingly the author states that the SS-Sturmbataillon 500 was an organic part of the 35.SS-Pol.Gren.Div. (Pipkorn) – according to Husemann (Die guten Glaubens waren II.) this unit was formed from the two regiments of the Pol.Brigade »Wirth« and the SS-Pol.Rgt.14 (Pol.Rgt. Greise).

Back to Porsch, according to Krätschmer and his own personal accounts the company destroyed its 100 enemy tank on 18 April in Marxdorf, a dutchmen van Brink was the lucky one. (note 35.SS-Pol.Gren.Div. was deployed around 100 km further to the south on the Oderfront).