Greeting from a puzzled Toy owner

I bought this 09 corolla for my son 3 months ago, it ran great until check eng. light came on but it went off by itself. So about three weeks ago it came back on and started shifting bad got a P0977 code shift solenoid B high current. Pulled plug on trans checked ohms on S1 S2 ST all read 12.3 ohms now what ? Cleared code new code P0354 cylinder 4 miss fire changed coils 4 with 3 new code P0351 cylinder 1 miss fire . I ordered all 4 coils oem and plugs. I have'nt got them yet I'm not sure what i should try next. Could a coil missfire cause the computor to throw out random code or ruin the computor