Mysql_upgrade fails, table is corrupted

I have a mariaDB, version 10.2.6-MariaDB mariadb.org binary distribution, with a table that is corrupted. It's useless data to me, so I've tried to drop the schema but it won't drop. Instead, it gives me this error when trying to drop it:

"Error Code: 1805. Column count of mysql.proc is wrong. Expected 20, found 21. The table is probably corrupted."

I've read on here that I should try to run a mysql_upgrade to fix this issue. But this also has failed when I point to the MariaDB bin directory and run this command line:

C:\Program Files\MariaDB 10.2\bin>mysql_upgrade --force -h localhost -uroot -p -
P3307
This is the results I get from it:

Phase 1/7: Checking and upgrading mysql database
Processing databases
mysql
mysql.column_stats OK
mysql.columns_priv OK
mysql.db OK
mysql.engine_cost OK
mysql.event OK
mysql.func OK
mysql.gtid_executed OK
mysql.gtid_slave_pos OK
mysql.help_category OK
mysql.help_keyword OK
mysql.help_relation OK
mysql.help_topic OK
mysql.host OK
mysql.index_stats OK
mysql.innodb_index_stats OK
mysql.innodb_table_stats OK
mysql.plugin OK
mysql.proc OK
mysql.procs_priv OK
mysql.proxies_priv OK
mysql.roles_mapping OK
mysql.server_cost OK
mysql.servers OK
mysql.slave_master_info OK
mysql.slave_relay_log_info OK
mysql.slave_worker_info OK
mysql.table_stats OK
mysql.tables_priv OK
mysql.time_zone OK
mysql.time_zone_leap_second OK
mysql.time_zone_name OK
mysql.time_zone_transition OK
mysql.time_zone_transition_type OK
mysql.transaction_registry OK
mysql.user OK
Phase 2/7: Installing used storage engines... Skipped
Phase 3/7: Fixing views
Phase 4/7: Running 'mysql_fix_privilege_tables'
ERROR 1408 (HY000) at line 545: Event Scheduler: An error occurred when initiali
zing system tables. Disabling the Event Scheduler.
ERROR 1805 (HY000) at line 572: Column count of mysql.proc is wrong. Expected 20
, found 21. The table is probably corrupted
ERROR 1805 (HY000) at line 574: Column count of mysql.proc is wrong. Expected 20
, found 21. The table is probably corrupted
ERROR 1805 (HY000) at line 582: Column count of mysql.proc is wrong. Expected 20
, found 21. The table is probably corrupted
ERROR 1805 (HY000) at line 584: Column count of mysql.proc is wrong. Expected 20
, found 21. The table is probably corrupted
FATAL ERROR: Upgrade failed
Any advice on how to resolve this?