I have no energy cost issues.
If you have no energy cost issues meaning that energy is not a problem with you,you either have a very cheap price for it or your devices are in a place where the energy bills are already paid in advance then it is worth mining in solo despite having only a small hash rate but even that small hash rate have some slight chances of getting a block and getting all the rewards from that block.
The best to do in your case though since electricity is no problem is to mine normally in a pool and stock up your doge every day a little,this is a sure reward while mining solo it can even be mining in vain if you don't manage to hit a block during the time you solo mine.
If he has no energy cost issues. He should mine at least 4 days on viabtc as pps. Maybe 5.
And mine solo for 2 or 3 days.
No energy issues means 0 cost. It seems he is saying he has free power.
So why not take $3.41 a day 5 days a week. or 3.41 x 261 = 890 usd for sure.
and maybe he gets lucky with the solo on the 104 days he mines solo.
To toss a certain $890 makes no sense to me.
He would need at least 2 solo blocks to do better.
My way he gets the $890 and could still get some solo blocks. By mining the 104 days solo.