1B913535 - 2012 150 Optimax Pro XS

A few days ago I had trouble starting my motor. It sounded like the starter was weak and not getting full power. Eventually it sounded normal and then started right up. I took it out again and it continues to do this. It is connected to an IONIC 125 AH battery and has been since before I bought it. The Bluetooth tells me the battery is plenty charged and giving proper voltage.

Here is what I have done to trouble shoot so far.

I removed the cowl. The gear pops up and turns but looks slow to me, not that I would know what right is.
I removed all wires but from battery except engine and console. Engine wire is connected directly to the battery.
Checked all connections on the engine.

Tested the battery while cranking, started at 12.75 volts and dropped to 11 - 11.5 volts while cranking.
Tested the connection before the attached solenoid and it about 12.75 and dropped to 5 - 6 volts while cranking.
Tested the connection after the attached solenoid and it was 0 before cranking and went to 5 - 6 volts while cranking.

I am thinking the solenoid is bad. Does this sound right? Is there something else I can do to test it.