are you sure the dtb files you sent are for android?
pls refer to the Table 2. Options for uuu_imx_android_flash tool, focus on -d dtb_feature:
Flashes dtbo and vbmeta images with "dtb_feature" in their names. For i.MX
8QuadMax MEK, it can be "md". For i.MX 8QuadXPlus MEK, do not use this option.
If this option is not used, default "dtbo-imx8qm.img" and "vbmeta-imx8qm.img" are
flashed for i.MX 8QuadMax MEK.
so for imx8qxp, should use vbmeta-imx8qxp.img and dtbo-imx8qxp.img, and all of board images are listed Table 1. Board images