Dapper Decimal Precision and Scale for SQL Server

DPA records a query that shows an INSERT to a table from Dapper.

The table has columns that have DECIMAL Precision as 18,8 and 18,4 which is a pretty wide berth in terms of being able to accept a wide variety of decimal values both before and after the decimal point.
However the commands show up in DPA for thousands of executions as DECIMAL(4,2).

@Price DECIMAL(4, 2),                    -- should be decimal(18,8)
@Quantity DECIMAL(6, 4),               -- should be a decimal(18,4)

This means it would accept values like 11.00000 but never 111.00000.

But our data seems to be inserting properly.
But when I test it, it errors out every time as the precision in scale are seemingly not right.
Dapper may be adjusting to the data that is coming in.
This may suggest a lot of busy work or very small numbers being flushed through the system.
Indeed, the number of ECS nodes is over 20 and the INSERTS are being sent to the database in the hundreds of thousands.

But wouldn't a plan be generated for the larger numbers?
Or is Dapper somehow fooling DPA?