Your source is "KTB 6.6.1944 ALA"? What, exactly, is "ALA"? That could be Artillerie-Lehr-Abteilung or even Aufklärungs-Lehr-Abteilung and not the "Pz Lehr division". Most likely, as of 6 June, the Artillerie-Lehr-Abteilung referred to the II./Panzer-Artillerie-Regiment 130., which had been formed from the Fahnenjunker of the Artillerie Schule Mourmelon. It nominally consisted of three batteries each of four 10.5cm leFH, but given the report includes both leFH and sFH rounds it seems likely they are referring to a tactical artillery grouping and not the actual organization. Furthermore, the only schwer feld haubitz in the division on that date were four 15cm sFH 18 in 8./Panzer-Artillerie-Regiment 130. (the other two batteries of the III. Abteilung -formerly s.Art.-Abtl. 985 - consisted of four 15.2cm KH 433 (r) and four 10cm K 18.
Fundamentally, we do not know exactly what was reported in your "source". The 1. Ausstattung of a leFH Abteilung was 2,700 rounds (1,770 HE, 378 AT, 216 CS, and 336 "special" (long range) rounds. In other words, about 900 rounds per battery. The 1. Ausstattung for a battery of sFH was 700 rounds (510 HE, 92 AT, and 98 CS). I suspect the report is for a tactical grouping of one leFH amd one sFH battery. Furthermore, only 22.9% of the 1. Ausstattung was carried with the firing battery. Another 33.3% was held by the Muni-Staffel of the regiment, and the remainder with the division Nachschub-Truppen.
Finally, there is simply no evidence that any of the German divisions in the west did not have access to at least its nominal 1. Ausstattung of artillery ammunition. In fact, we know for example that 352. Inf-Div had and fired off its entire 1. Ausstattung on D-Day. The real problem was the German inability to maintain a steady stream of resupply from the Heeres-Muni-Lagern to the divisions.
Much the same applies here. Given its inclusion, Aufklärungs-Lehr-Abteilung remains a possibilityInfantry: 500 mortar rounds 254 for light inf guns 147 for heavy inf guns