Georeferencing a historic map to a local custom coordinate system

I want to georeference a map (TIFF) from 1965 using the grid crosses as ground control points. The map is in the local coordinate system which I calculated and wrote a custom coordinate system for.

When I want to start the georeferencing it says transformation is not possible. I am afraid it doesn’t work because of my custom coordinate reference system. If I use another system it "works" ( but then the map is wrong obviously).

DERIVEDPROJCRS["Milet lokal 2015 (Bendt)",
    BASEPROJCRS["WGS84 / UTM zone 35N",
        BASEGEOGCRS["WGS 84",
            DATUM["World Geodetic System 1984",
                ELLIPSOID["WGS 84",6378137,298.257223563,
                    LENGTHUNIT["metre",1]]],
            PRIMEM["Greenwich",0,
                ANGLEUNIT["degree",0.0174532925199433]]],
        CONVERSION["UTM zone 35N",
            METHOD["Transverse Mercator",
                ID["EPSG",9807]],
            PARAMETER["Latitude of natural origin",0,
                ANGLEUNIT["degree",0.0174532925199433],
                ID["EPSG",8801]],
            PARAMETER["Longitude of natural origin",27,
                ANGLEUNIT["degree",0.0174532925199433],
                ID["EPSG",8802]],
            PARAMETER["Scale factor at natural origin",0.9996,
                SCALEUNIT["unity",1],
                ID["EPSG",8805]],
            PARAMETER["False easting",500000,
                LENGTHUNIT["metre",1],
                ID["EPSG",8806]],
            PARAMETER["False northing",0,
                LENGTHUNIT["metre",1],
                ID["EPSG",8807]]]],
    DERIVINGCONVERSION["Affine",
        METHOD["Affine parametric transformation",
            ID["EPSG",9624]],
        PARAMETER["A0",-428178.87985533,
            LENGTHUNIT["metre",1],
            ID["EPSG",8623]],
        PARAMETER["A1",1.00014514665939,
            SCALEUNIT["coefficient",1],
            ID["EPSG",8624]],
        PARAMETER["A2",-0.0227055108057824,
            SCALEUNIT["coefficient",1],
            ID["EPSG",8625]],
        PARAMETER["B0",-4164309.21582976,
            LENGTHUNIT["metre",1],
            ID["EPSG",8639]],
        PARAMETER["B1",0.0227055108057824,
            SCALEUNIT["coefficient",1],
            ID["EPSG",8640]],
        PARAMETER["B2",1.00014514665939,
            SCALEUNIT["coefficient",1],
            ID["EPSG",8641]]],
    CS[Cartesian,2],
        AXIS["(E)",east,
            ORDER[1],
            LENGTHUNIT["metre",1]],
        AXIS["(N)",north,
            ORDER[2],
            LENGTHUNIT["metre",1]]]

Also my QGIS version 3.16 is not the problem. I tried with version 3.10.

Is there a way to georeference a TIFF to my custom coordinate system?