DUMP_TMC stepper_y
========== Write-only registers ==========
SLAVECONF: 00000200 senddelay=2
IHOLD_IRUN: 00081919 ihold=25 irun=25 iholddelay=8
TPOWERDOWN: 00000014 tpowerdown=20
SGTHRS: 00000000
========== Queried registers ==========
GCONF: 000001c4 en_spreadcycle=1 pdn_disable=1 mstep_reg_select=1 multistep_filt=1
GSTAT: 00000000
IFCNT: 0000004e ifcnt=78
OTP_READ: 00000010 otp_fclktrim=16
IOIN: 21000040 pdn_uart=1 version=0x21
FACTORY_CONF: 00000010 fclktrim=16
TSTEP: 000fffff tstep=1048575
MSCNT: 00000008 mscnt=8
MSCURACT: 00f7000c cur_a=12 cur_b=247
CHOPCONF: 34030053 toff=3 hstrt=5 tbl=2 vsense=1 mres=4(16usteps) intpol=1 dedge=1
DRV_STATUS: 80190080 olb=1(OpenLoad_B!) cs_actual=25 stst=1
PWMCONF: c80d0e24 pwm_ofs=36 pwm_grad=14 pwm_freq=1 pwm_autoscale=1 pwm_autograd=1 pwm_reg=8 pwm_lim=12
PWM_SCALE: 0000001d pwm_scale_sum=29
PWM_AUTO: 000e0024 pwm_ofs_auto=36 pwm_grad_auto=14
SG_RESULT: 00000002 sg_result=2
This is your output of DUMP_TMC STEPPER=stepper_y
DRV_STATUS: 80190080 olb=1(OpenLoad_B!) cs_actual=25 stst=1 shows that the TMC is not happy.
Since you verified that it is not the TMC itself, then we likely have an issue with the stepper. In my 3D printing career I have not had a dead stepper but quite some wiring issue.
Check the wiring again, especially on the boards side. Use a fine pliers to gently pull on each cable individually. Inspect the entire harness etc. If it does not help, try exchanging the stepper