I had a problem similar to this in MySQL 5.7: Table is marked as crashed and should be repaired
When I used the tips in the thread to repair, the following happens:
REPAIR TABLE `<table>`
"database.<table>" "repair" "Error" "Table ‘database.<table>' doesn't exist" "database.<table>" "repair" "status" "Operation failed"
When I click on the table in HeidiSQL, I can view it normally. It only fails when I run a query.