Need help from the Technical guys!

[mule#1]

I recently added a MK V to the fold and I'm having an issue. I plugged in tonight and no sound! Only the 5U4 rectifier tube was glowing and none of 4 6L6's. Then I found preamp tubes V1, V2 and V5 were working but 3,4,6 & 7 are not glowing. I find it odd 4 would blow at once. However 7 is the driver/phase inverter. If that is blown will the 6L6's not work? Can one blown 12AX7 affect another?

I appreciate your help!