Investing with a Spouse

Hi everyone. I’m newish to this investment journey, so please bear with me.

My husband (39M) and I (35F) are on our investing journey and we’re trying to invest 20% of our income into investments. Both of us make 120k annually before taxes. He works for Rogers and puts into an Employer Savings Plan (not 100% on the naming) which basically is 18% of his gross paycheque goes to buying Rogers stock and then the employer matches 50%. This is a non-registered account. So at the end of it all, he has only about 2% to invest in other ETFs outside of Rogers.

I work in the healthcare industry so instead i invest my 20% into WS RRSP and TFSA ETFs.

My question is if its okay if he keeps his investment strategy this way? Since I am investing into a more diverse portfolio, i’m hoping this offsets/balances out his non-diversified portfolio?

Are we at risk if Rogers stocks plummet? (They currently arent doing very well after the Shaw merge). Its the employer match which is keeping him locked in.

Please let me know if i’ve missed any details.